642406404 has 24 divisors (see below), whose sum is σ = 1587122208. Its totient is φ = 201539200.

The previous prime is 642406393. The next prime is 642406417. The reversal of 642406404 is 404604246.

It is a super-3 number, since 3×642406404³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1574322 + ... + 1574729.

It is an arithmetic number, because the mean of its divisors is an integer number (66130092).

Almost surely, 2^642406404 is an apocalyptic number.

It is an amenable number.

642406404 is an abundant number, since it is smaller than the sum of its proper divisors (944715804).

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

642406404 is a wasteful number, since it uses less digits than its factorization.

642406404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3149075 (or 3149073 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 30.

The square root of 642406404 is about 25345.7373931002. The cubic root of 642406404 is about 862.8526168362.

The spelling of 642406404 in words is "six hundred forty-two million, four hundred six thousand, four hundred four".