21573577464 has 32 divisors (see below), whose sum is σ = 53967727440. Its totient is φ = 7186688000.

The previous prime is 21573577453. The next prime is 21573577499. The reversal of 21573577464 is 46477537512.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 242307 + ... + 319154.

Almost surely, 2^21573577464 is an apocalyptic number.

21573577464 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21573577464 is an abundant number, since it is smaller than the sum of its proper divisors (32394149976).

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

21573577464 is a wasteful number, since it uses less digits than its factorization.

21573577464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 563071 (or 563067 counting only the distinct ones).

The product of its digits is 4939200, while the sum is 51.

The spelling of 21573577464 in words is "twenty-one billion, five hundred seventy-three million, five hundred seventy-seven thousand, four hundred sixty-four".