644060004 has 24 divisors (see below), whose sum is σ = 1717493568. Its totient is φ = 184017120.

The previous prime is 644060003. The next prime is 644060009. The reversal of 644060004 is 400060446.

It is not an unprimeable number, because it can be changed into a prime (644060003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3833607 + ... + 3833774.

It is an arithmetic number, because the mean of its divisors is an integer number (71562232).

Almost surely, 2^644060004 is an apocalyptic number.

It is an amenable number.

644060004 is an abundant number, since it is smaller than the sum of its proper divisors (1073433564).

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

644060004 is a wasteful number, since it uses less digits than its factorization.

644060004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7667395 (or 7667393 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 644060004 is about 25378.3372977821. The cubic root of 644060004 is about 863.5923306095.

The spelling of 644060004 in words is "six hundred forty-four million, sixty thousand, four".