646635668457024 has 147 divisors (see below), whose sum is σ = 1923887736278427. Its totient is φ = 215543391928704.

The previous prime is 646635668457013. The next prime is 646635668457049. The reversal of 646635668457024 is 420754866536646.

It is a happy number.

The square root of 646635668457024 is 25429032.

It is a perfect power (a square), and thus also a powerful number.

646635668457024 is a `hidden beast` number, since 6 + 4 + 6 + 6 + 3 + 566 + 8 + 4 + 57 + 0 + 2 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 5492612049 + ... + 5492729775.

Almost surely, 2^{646635668457024} is an apocalyptic number.

646635668457024 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

646635668457024 is the 25429032-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646635668457024

646635668457024 is an abundant number, since it is smaller than the sum of its proper divisors (1277252067821403).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646635668457024 is an frugal number, since it uses more digits than its factorization.

646635668457024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235484 (or 117732 counting only the distinct ones).

The product of its (nonzero) digits is 4180377600, while the sum is 72.

The spelling of 646635668457024 in words is "six hundred forty-six trillion, six hundred thirty-five billion, six hundred sixty-eight million, four hundred fifty-seven thousand, twenty-four".