3644640221604 has 24 divisors (see below), whose sum is σ = 8591832277728. Its totient is φ = 1202355536640.

The previous prime is 3644640221513. The next prime is 3644640221647. The reversal of 3644640221604 is 4061220464463.

It is a happy number.

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, 1565565942 + ... + 1565568269.

It is an arithmetic number, because the mean of its divisors is an integer number (357993011572).

Almost surely, 2^{3644640221604} is an apocalyptic number.

It is an amenable number.

3644640221604 is an abundant number, since it is smaller than the sum of its proper divisors (4947192056124).

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

3644640221604 is a wasteful number, since it uses less digits than its factorization.

3644640221604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3131134315 (or 3131134313 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 42.

The spelling of 3644640221604 in words is "three trillion, six hundred forty-four billion, six hundred forty million, two hundred twenty-one thousand, six hundred four".