642873944 has 16 divisors (see below), whose sum is σ = 1205698200. Its totient is φ = 321354432.

The previous prime is 642873919. The next prime is 642873983. The reversal of 642873944 is 449378246.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33959 + ... + 49385.

Almost surely, 2^642873944 is an apocalyptic number.

It is an amenable number.

642873944 is a deficient number, since it is larger than the sum of its proper divisors (562824256).

642873944 is a wasteful number, since it uses less digits than its factorization.

642873944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20642 (or 20638 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 47.

The square root of 642873944 is about 25354.9589626960. The cubic root of 642873944 is about 863.0618926057.

The spelling of 642873944 in words is "six hundred forty-two million, eight hundred seventy-three thousand, nine hundred forty-four".