Go

func isPalindrome(x int) bool {
    if x < 0 {
        return false
    }

    res, val := 0, x
    for x != 0 {
        res = res * 10 + x % 10
        x /= 10
    }

    return res == val
}

Python3

class Solution:
    def isPalindrome(self, x: int) -> bool:
        if x < 0 : return False

        val, res = x, 0
        while x:
            res = res * 10 + x % 10
            x //= 10
        return res == val

class Solution:
    def isPalindrome(self, x: int) -> bool:
        return str(x) == str(x)[::-1]