642552564 has 72 divisors (see below), whose sum is σ = 1651406400. Its totient is φ = 194059008.

The previous prime is 642552523. The next prime is 642552577. The reversal of 642552564 is 465255246.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 96412 + ... + 102860.

It is an arithmetic number, because the mean of its divisors is an integer number (22936200).

Almost surely, 2^642552564 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642552564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (825703200).

642552564 is an abundant number, since it is smaller than the sum of its proper divisors (1008853836).

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

642552564 is a wasteful number, since it uses less digits than its factorization.

642552564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6517 (or 6496 counting only the distinct ones).

The product of its digits is 288000, while the sum is 39.

The square root of 642552564 is about 25348.6205541840. The cubic root of 642552564 is about 862.9180504799.

The spelling of 642552564 in words is "six hundred forty-two million, five hundred fifty-two thousand, five hundred sixty-four".