21868808 has 16 divisors (see below), whose sum is σ = 44158380. Its totient is φ = 10093248.

The previous prime is 21868793. The next prime is 21868831. The reversal of 21868808 is 80886812.

It can be written as a sum of positive squares in 2 ways, for example, as 19731364 + 2137444 = 4442^2 + 1462^2 .

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, 105035 + ... + 105242.

Almost surely, 2^21868808 is an apocalyptic number.

It is an amenable number.

21868808 is an abundant number, since it is smaller than the sum of its proper divisors (22289572).

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

21868808 is a wasteful number, since it uses less digits than its factorization.

21868808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210296 (or 210292 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 41.

The square root of 21868808 is about 4676.4097339733. The cubic root of 21868808 is about 279.6458447561.

The spelling of 21868808 in words is "twenty-one million, eight hundred sixty-eight thousand, eight hundred eight".