1644640504 has 32 divisors (see below), whose sum is σ = 3351967920. Its totient is φ = 751965696.

The previous prime is 1644640471. The next prime is 1644640511. The reversal of 1644640504 is 4050464461.

It is a self number, because there is not a number n which added to its sum of digits gives 1644640504.

It is a congruent 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, 62769 + ... + 85024.

Almost surely, 2^1644640504 is an apocalyptic number.

It is an amenable number.

1644640504 is an abundant number, since it is smaller than the sum of its proper divisors (1707327416).

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

1644640504 is a wasteful number, since it uses less digits than its factorization.

1644640504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147919 (or 147915 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 34.

The square root of 1644640504 is about 40554.1675293674. The cubic root of 1644640504 is about 1180.3849419192.

The spelling of 1644640504 in words is "one billion, six hundred forty-four million, six hundred forty thousand, five hundred four".