642865400 has 24 divisors (see below), whose sum is σ = 1494662520. Its totient is φ = 257146080.

The previous prime is 642865373. The next prime is 642865403. The reversal of 642865400 is 4568246.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642865403) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1606964 + ... + 1607363.

It is an arithmetic number, because the mean of its divisors is an integer number (62277605).

Almost surely, 2^642865400 is an apocalyptic number.

It is an amenable number.

642865400 is an abundant number, since it is smaller than the sum of its proper divisors (851797120).

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

642865400 is a wasteful number, since it uses less digits than its factorization.

642865400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3214343 (or 3214334 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 35.

The square root of 642865400 is about 25354.7904743857. The cubic root of 642865400 is about 863.0580691327.

The spelling of 642865400 in words is "six hundred forty-two million, eight hundred sixty-five thousand, four hundred".