21381592 has 16 divisors (see below), whose sum is σ = 40296960. Its totient is φ = 10635744.

The previous prime is 21381557. The next prime is 21381611. The reversal of 21381592 is 29518312.

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, 5208 + ... + 8359.

It is an arithmetic number, because the mean of its divisors is an integer number (2518560).

Almost surely, 2^21381592 is an apocalyptic number.

It is an amenable number.

21381592 is a deficient number, since it is larger than the sum of its proper divisors (18915368).

21381592 is a wasteful number, since it uses less digits than its factorization.

21381592 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13770 (or 13766 counting only the distinct ones).

The product of its digits is 4320, while the sum is 31.

The square root of 21381592 is about 4624.0233563424. The cubic root of 21381592 is about 277.5534815623.

The spelling of 21381592 in words is "twenty-one million, three hundred eighty-one thousand, five hundred ninety-two".