21531304037524 has 24 divisors (see below), whose sum is σ = 37788002013440. Its totient is φ = 10734740653536.

The previous prime is 21531304037501. The next prime is 21531304037527. The reversal of 21531304037524 is 42573040313512.

It is a super-3 number, since 3×21531304037524³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21531304037527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8951089 + ... + 11098855.

Almost surely, 2^{21531304037524} is an apocalyptic number.

It is an amenable number.

21531304037524 is a deficient number, since it is larger than the sum of its proper divisors (16256697975916).

21531304037524 is a wasteful number, since it uses less digits than its factorization.

21531304037524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2154967 (or 2154965 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 40.

The spelling of 21531304037524 in words is "twenty-one trillion, five hundred thirty-one billion, three hundred four million, thirty-seven thousand, five hundred twenty-four".