21533168 has 20 divisors (see below), whose sum is σ = 42106680. Its totient is φ = 10666944.

The previous prime is 21533143. The next prime is 21533177. The reversal of 21533168 is 86133512.

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21533168.

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, 4430 + ... + 7917.

It is an arithmetic number, because the mean of its divisors is an integer number (2105334).

Almost surely, 2^21533168 is an apocalyptic number.

It is an amenable number.

21533168 is a deficient number, since it is larger than the sum of its proper divisors (20573512).

21533168 is a wasteful number, since it uses less digits than its factorization.

21533168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12464 (or 12458 counting only the distinct ones).

The product of its digits is 4320, while the sum is 29.

The square root of 21533168 is about 4640.3844668303. The cubic root of 21533168 is about 278.2078048777.

The spelling of 21533168 in words is "twenty-one million, five hundred thirty-three thousand, one hundred sixty-eight".