21357892 has 24 divisors (see below), whose sum is σ = 39485376. Its totient is φ = 10087968.

The previous prime is 21357871. The next prime is 21357901. The reversal of 21357892 is 29875312.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6238 + ... + 9034.

It is an arithmetic number, because the mean of its divisors is an integer number (1645224).

Almost surely, 2^21357892 is an apocalyptic number.

It is an amenable number.

21357892 is a deficient number, since it is larger than the sum of its proper divisors (18127484).

21357892 is a wasteful number, since it uses less digits than its factorization.

21357892 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2907 (or 2905 counting only the distinct ones).

The product of its digits is 30240, while the sum is 37.

The square root of 21357892 is about 4621.4599424857. The cubic root of 21357892 is about 277.4508941055.

The spelling of 21357892 in words is "twenty-one million, three hundred fifty-seven thousand, eight hundred ninety-two".