643358976 has 72 divisors (see below), whose sum is σ = 1844015040. Its totient is φ = 197953536.

The previous prime is 643358971. The next prime is 643359023. The reversal of 643358976 is 679853346.

It is not an unprimeable number, because it can be changed into a prime (643358971) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22236 + ... + 42203.

It is an arithmetic number, because the mean of its divisors is an integer number (25611320).

Almost surely, 2^643358976 is an apocalyptic number.

It is an amenable number.

643358976 is an abundant number, since it is smaller than the sum of its proper divisors (1200656064).

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

643358976 is a wasteful number, since it uses less digits than its factorization.

643358976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64471 (or 64457 counting only the distinct ones).

The product of its digits is 3265920, while the sum is 51.

The square root of 643358976 is about 25364.5219943132. The cubic root of 643358976 is about 863.2788907727.

The spelling of 643358976 in words is "six hundred forty-three million, three hundred fifty-eight thousand, nine hundred seventy-six".