21122544512 has 16 divisors (see below), whose sum is σ = 42080069400. Its totient is φ = 10561272192.

The previous prime is 21122544503. The next prime is 21122544593. The reversal of 21122544512 is 21544522112.

It is a tau number, because it is divible by the number of its divisors (16).

It is a super-2 number, since 2×21122544512² (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 (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82509812 + ... + 82510067.

Almost surely, 2^21122544512 is an apocalyptic number.

It is an amenable number.

21122544512 is a deficient number, since it is larger than the sum of its proper divisors (20957524888).

21122544512 is an equidigital number, since it uses as much as digits as its factorization.

21122544512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165019893 (or 165019881 counting only the distinct ones).

The product of its digits is 6400, while the sum is 29.

The spelling of 21122544512 in words is "twenty-one billion, one hundred twenty-two million, five hundred forty-four thousand, five hundred twelve".