21512023536 has 20 divisors (see below), whose sum is σ = 55572727592. Its totient is φ = 7170674496.

The previous prime is 21512023513. The next prime is 21512023597. The reversal of 21512023536 is 63532021512.

It is a super-2 number, since 2×21512023536² (a number of 21 digits) contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 224083531 + ... + 224083626.

Almost surely, 2^21512023536 is an apocalyptic number.

It is an amenable number.

21512023536 is an abundant number, since it is smaller than the sum of its proper divisors (34060704056).

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

21512023536 is a wasteful number, since it uses less digits than its factorization.

21512023536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 448167168 (or 448167162 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 30.

The spelling of 21512023536 in words is "twenty-one billion, five hundred twelve million, twenty-three thousand, five hundred thirty-six".