math/big: cast string "24994434550311665182" to *big.Int resolves in invalid instance

[sham789]

What version of Go are you using (go version)?

$ go version
go version go1.15.2 darwin/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GO111MODULE="on"
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/shamil/Library/Caches/go-build"
GOENV="/Users/shamil/Library/Application Support/go/env"
GOEXE=""
GOFLAGS=" -mod="
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOINSECURE=""
GOMODCACHE="/Users/shamil/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="darwin"
GOPATH="/Users/shamil/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/usr/local/var/www/susy-ping-pong-bot/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/w5/s3w49d_j2vg9p5xjv7dl4bdh0000gn/T/go-build800082162=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

https://play.golang.org/p/AmEckBDqrFo

What did you expect to see?

I expect to see that "24994434550311665182" string casts to valid *big.Int.
With appropriate true results while calling .IsInt64() and .IsUint64()

What did you see instead?

Instead, I see that "24994434550311665182" cast string is invalid *big.Int instance.
When I try to retrieve .Int64() I see "6547690476602113566".

[ALTree]

24994434550311665182 is both bigger that the biggest positive signed int64 and bigger than the biggest unsigned uint64 , so your expectation seems wrong.

[sham789]

Thank you