643924952 has 16 divisors (see below), whose sum is σ = 1317119400. Its totient is φ = 292693120.

The previous prime is 643924933. The next prime is 643924979. The reversal of 643924952 is 259429346.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3658577 + ... + 3658752.

Almost surely, 2^643924952 is an apocalyptic number.

It is an amenable number.

643924952 is an abundant number, since it is smaller than the sum of its proper divisors (673194448).

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

643924952 is a wasteful number, since it uses less digits than its factorization.

643924952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7317346 (or 7317342 counting only the distinct ones).

The product of its digits is 466560, while the sum is 44.

The square root of 643924952 is about 25375.6763850740. The cubic root of 643924952 is about 863.5319645858.

The spelling of 643924952 in words is "six hundred forty-three million, nine hundred twenty-four thousand, nine hundred fifty-two".