21515892572 has 6 divisors (see below), whose sum is σ = 37652812008. Its totient is φ = 10757946284.

The previous prime is 21515892571. The next prime is 21515892589. The reversal of 21515892572 is 27529851512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21515892571) by changing a digit.

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 as a sum of consecutive naturals, namely, 2689486568 + ... + 2689486575.

It is an arithmetic number, because the mean of its divisors is an integer number (6275468668).

Almost surely, 2^21515892572 is an apocalyptic number.

It is an amenable number.

21515892572 is a deficient number, since it is larger than the sum of its proper divisors (16136919436).

21515892572 is a wasteful number, since it uses less digits than its factorization.

21515892572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5378973147 (or 5378973145 counting only the distinct ones).

The product of its digits is 504000, while the sum is 47.

The spelling of 21515892572 in words is "twenty-one billion, five hundred fifteen million, eight hundred ninety-two thousand, five hundred seventy-two".