21105996 has 24 divisors (see below), whose sum is σ = 51389184. Its totient is φ = 6729360.

The previous prime is 21105977. The next prime is 21106037. The reversal of 21105996 is 69950112.

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, 37960 + ... + 38511.

It is an arithmetic number, because the mean of its divisors is an integer number (2141216).

Almost surely, 2^21105996 is an apocalyptic number.

It is an amenable number.

21105996 is an abundant number, since it is smaller than the sum of its proper divisors (30283188).

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

21105996 is a wasteful number, since it uses less digits than its factorization.

21105996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76501 (or 76499 counting only the distinct ones).

The product of its (nonzero) digits is 4860, while the sum is 33.

The square root of 21105996 is about 4594.1262498978. The cubic root of 21105996 is about 276.3558212687.

The spelling of 21105996 in words is "twenty-one million, one hundred five thousand, nine hundred ninety-six".