21123012324 has 24 divisors (see below), whose sum is σ = 49290595200. Its totient is φ = 7040494624.

The previous prime is 21123012311. The next prime is 21123012353. The reversal of 21123012324 is 42321032112.

It is a self number, because there is not a number n which added to its sum of digits gives 21123012324.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133477 + ... + 245075.

It is an arithmetic number, because the mean of its divisors is an integer number (2053774800).

Almost surely, 2^21123012324 is an apocalyptic number.

It is an amenable number.

21123012324 is an abundant number, since it is smaller than the sum of its proper divisors (28167582876).

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

21123012324 is a wasteful number, since it uses less digits than its factorization.

21123012324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127379 (or 127377 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21123012324 its reverse (42321032112), we get a palindrome (63444044436).

The spelling of 21123012324 in words is "twenty-one billion, one hundred twenty-three million, twelve thousand, three hundred twenty-four".