643866612 has 24 divisors (see below), whose sum is σ = 1502774112. Its totient is φ = 214562400.

The previous prime is 643866611. The next prime is 643866667. The reversal of 643866612 is 216668346.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643866611) 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, 67287 + ... + 76257.

It is an arithmetic number, because the mean of its divisors is an integer number (62615588).

Almost surely, 2^643866612 is an apocalyptic number.

It is an amenable number.

643866612 is an abundant number, since it is smaller than the sum of its proper divisors (858907500).

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

643866612 is a wasteful number, since it uses less digits than its factorization.

643866612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14959 (or 14957 counting only the distinct ones).

The product of its digits is 248832, while the sum is 42.

The square root of 643866612 is about 25374.5268330269. The cubic root of 643866612 is about 863.5058849544.

The spelling of 643866612 in words is "six hundred forty-three million, eight hundred sixty-six thousand, six hundred twelve".