21473753872 has 20 divisors (see below), whose sum is σ = 42287455756. Its totient is φ = 10560862080.

The previous prime is 21473753843. The next prime is 21473753891. The reversal of 21473753872 is 27835737412.

It can be written as a sum of positive squares in 2 ways, for example, as 5937627136 + 15536126736 = 77056^2 + 124644^2 .

It is a super-2 number, since 2×21473753872² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10999923 + ... + 11001874.

Almost surely, 2^21473753872 is an apocalyptic number.

It is an amenable number.

21473753872 is a deficient number, since it is larger than the sum of its proper divisors (20813701884).

21473753872 is a wasteful number, since it uses less digits than its factorization.

21473753872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22001866 (or 22001860 counting only the distinct ones).

The product of its digits is 1975680, while the sum is 49.

The spelling of 21473753872 in words is "twenty-one billion, four hundred seventy-three million, seven hundred fifty-three thousand, eight hundred seventy-two".