642351056 has 20 divisors (see below), whose sum is σ = 1252487172. Its totient is φ = 319128576.

The previous prime is 642351049. The next prime is 642351077. The reversal of 642351056 is 650153246.

It can be written as a sum of positive squares in 2 ways, for example, as 436141456 + 206209600 = 20884^2 + 14360^2 .

It is a super-2 number, since 2×642351056² = 825229758288630272, which contains 22 as substring.

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, 125345 + ... + 130368.

Almost surely, 2^642351056 is an apocalyptic number.

It is an amenable number.

642351056 is a deficient number, since it is larger than the sum of its proper divisors (610136116).

642351056 is a wasteful number, since it uses less digits than its factorization.

642351056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255878 (or 255872 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 642351056 is about 25344.6455094562. The cubic root of 642351056 is about 862.8278357745.

The spelling of 642351056 in words is "six hundred forty-two million, three hundred fifty-one thousand, fifty-six".