646644330 has 64 divisors (see below), whose sum is σ = 1761108480. Its totient is φ = 168766272.

The previous prime is 646644253. The next prime is 646644337. The reversal of 646644330 is 33446646.

646644330 is a `hidden beast` number, since 6 + 4 + 6 + 644 + 3 + 3 + 0 = 666.

It is a super-2 number, since 2×646644330² = 836297779042297800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (646644337) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12789 + ... + 38168.

It is an arithmetic number, because the mean of its divisors is an integer number (27517320).

Almost surely, 2^646644330 is an apocalyptic number.

646644330 is an abundant number, since it is smaller than the sum of its proper divisors (1114464150).

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

646644330 is a wasteful number, since it uses less digits than its factorization.

646644330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51020 (or 51014 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 36.

The square root of 646644330 is about 25429.2023075833. The cubic root of 646644330 is about 864.7458596065.

The spelling of 646644330 in words is "six hundred forty-six million, six hundred forty-four thousand, three hundred thirty".