21015368 has 32 divisors (see below), whose sum is σ = 45252000. Its totient is φ = 9048960.

The previous prime is 21015317. The next prime is 21015391. The reversal of 21015368 is 86351012.

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, 4613 + ... + 7956.

It is an arithmetic number, because the mean of its divisors is an integer number (1414125).

Almost surely, 2^21015368 is an apocalyptic number.

It is an amenable number.

21015368 is an abundant number, since it is smaller than the sum of its proper divisors (24236632).

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

21015368 is a wasteful number, since it uses less digits than its factorization.

21015368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12605 (or 12601 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 21015368 is about 4584.2521745646. The cubic root of 21015368 is about 275.9597014607.

The spelling of 21015368 in words is "twenty-one million, fifteen thousand, three hundred sixty-eight".