21310912 has 28 divisors (see below), whose sum is σ = 48331120. Its totient is φ = 9133056.

The previous prime is 21310909. The next prime is 21310921. The reversal of 21310912 is 21901312.

It is a tau number, because it is divible by the number of its divisors (28).

It is a self number, because there is not a number n which added to its sum of digits gives 21310912.

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, 23337 + ... + 24232.

Almost surely, 2^21310912 is an apocalyptic number.

It is an amenable number.

21310912 is an abundant number, since it is smaller than the sum of its proper divisors (27020208).

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

21310912 is an equidigital number, since it uses as much as digits as its factorization.

21310912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47588 (or 47578 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 21310912 is about 4616.3743349083. The cubic root of 21310912 is about 277.2473126543.

It can be divided in two parts, 21310 and 912, that added together give a palindrome (22222).

The spelling of 21310912 in words is "twenty-one million, three hundred ten thousand, nine hundred twelve".