21335168 has 32 divisors (see below), whose sum is σ = 44357760. Its totient is φ = 10202368.

The previous prime is 21335143. The next prime is 21335173. The reversal of 21335168 is 86153312.

It is a tau number, because it is divible by the number of its divisors (32).

It is a self number, because there is not a number n which added to its sum of digits gives 21335168.

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, 680 + ... + 6567.

It is an arithmetic number, because the mean of its divisors is an integer number (1386180).

Almost surely, 2^21335168 is an apocalyptic number.

It is an amenable number.

21335168 is an abundant number, since it is smaller than the sum of its proper divisors (23022592).

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

21335168 is an equidigital number, since it uses as much as digits as its factorization.

21335168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7284 (or 7272 counting only the distinct ones).

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

The square root of 21335168 is about 4619.0007577397. Note that the first 3 decimals coincide. The cubic root of 21335168 is about 277.3524600550.

The spelling of 21335168 in words is "twenty-one million, three hundred thirty-five thousand, one hundred sixty-eight".