21113120512 has 36 divisors (see below), whose sum is σ = 45975025656. Its totient is φ = 9596871680.

The previous prime is 21113120491. The next prime is 21113120533. The reversal of 21113120512 is 21502131112.

It is an interprime number because it is at equal distance from previous prime (21113120491) and next prime (21113120533).

It is a self number, because there is not a number n which added to its sum of digits gives 21113120512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3745963 + ... + 3751594.

It is an arithmetic number, because the mean of its divisors is an integer number (1277084046).

Almost surely, 2^21113120512 is an apocalyptic number.

21113120512 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21113120512 is an abundant number, since it is smaller than the sum of its proper divisors (24861905144).

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

21113120512 is an equidigital number, since it uses as much as digits as its factorization.

21113120512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7497584 (or 7497570 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 19.

Adding to 21113120512 its reverse (21502131112), we get a palindrome (42615251624).

The spelling of 21113120512 in words is "twenty-one billion, one hundred thirteen million, one hundred twenty thousand, five hundred twelve".