642511056 has 160 divisors (see below), whose sum is σ = 1959303168. Its totient is φ = 179230720.

The previous prime is 642511027. The next prime is 642511069. The reversal of 642511056 is 650115246.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 421111 + ... + 422633.

Almost surely, 2^642511056 is an apocalyptic number.

642511056 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642511056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (979651584).

642511056 is an abundant number, since it is smaller than the sum of its proper divisors (1316792112).

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

642511056 is a wasteful number, since it uses less digits than its factorization.

642511056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1609 (or 1603 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 642511056 is about 25347.8017981836. The cubic root of 642511056 is about 862.8994689787.

The spelling of 642511056 in words is "six hundred forty-two million, five hundred eleven thousand, fifty-six".