21113912 has 8 divisors (see below), whose sum is σ = 39588600. Its totient is φ = 10556952.

The previous prime is 21113887. The next prime is 21113927. The reversal of 21113912 is 21931112.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1319612 + ... + 1319627.

It is an arithmetic number, because the mean of its divisors is an integer number (4948575).

Almost surely, 2^21113912 is an apocalyptic number.

It is an amenable number.

21113912 is a deficient number, since it is larger than the sum of its proper divisors (18474688).

21113912 is a wasteful number, since it uses less digits than its factorization.

21113912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2639245 (or 2639241 counting only the distinct ones).

The product of its digits is 108, while the sum is 20.

The square root of 21113912 is about 4594.9877040097. The cubic root of 21113912 is about 276.3903668901.

The spelling of 21113912 in words is "twenty-one million, one hundred thirteen thousand, nine hundred twelve".