644974423468 has 12 divisors (see below), whose sum is σ = 1128819517000. Its totient is φ = 322454561472.

The previous prime is 644974423447. The next prime is 644974423487. The reversal of 644974423468 is 864324479446.

It is a hoax number, since the sum of its digits (61) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8118093 + ... + 8197156.

Almost surely, 2^644974423468 is an apocalyptic number.

It is an amenable number.

644974423468 is a deficient number, since it is larger than the sum of its proper divisors (483845093532).

644974423468 is a wasteful number, since it uses less digits than its factorization.

644974423468 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16325136 (or 16325134 counting only the distinct ones).

The product of its digits is 111476736, while the sum is 61.

The spelling of 644974423468 in words is "six hundred forty-four billion, nine hundred seventy-four million, four hundred twenty-three thousand, four hundred sixty-eight".