21488164 has 36 divisors (see below), whose sum is σ = 41477184. Its totient is φ = 9721008.

The previous prime is 21488143. The next prime is 21488171. The reversal of 21488164 is 46188412.

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

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 11 ways as a sum of consecutive naturals, for example, 32889 + ... + 33535.

It is an arithmetic number, because the mean of its divisors is an integer number (1152144).

Almost surely, 2^21488164 is an apocalyptic number.

It is an amenable number.

21488164 is a deficient number, since it is larger than the sum of its proper divisors (19989020).

21488164 is a wasteful number, since it uses less digits than its factorization.

21488164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 712 (or 691 counting only the distinct ones).

The product of its digits is 12288, while the sum is 34.

The square root of 21488164 is about 4635.5327633402. The cubic root of 21488164 is about 278.0138529750.

The spelling of 21488164 in words is "twenty-one million, four hundred eighty-eight thousand, one hundred sixty-four".