21955408 has 20 divisors (see below), whose sum is σ = 42665920. Its totient is φ = 10944864.

The previous prime is 21955399. The next prime is 21955411. The reversal of 21955408 is 80455912.

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, 4003 + ... + 7741.

It is an arithmetic number, because the mean of its divisors is an integer number (2133296).

Almost surely, 2^21955408 is an apocalyptic number.

It is an amenable number.

21955408 is a deficient number, since it is larger than the sum of its proper divisors (20710512).

21955408 is a wasteful number, since it uses less digits than its factorization.

21955408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4114 (or 4108 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 34.

The square root of 21955408 is about 4685.6598254675. The cubic root of 21955408 is about 280.0144890461.

The spelling of 21955408 in words is "twenty-one million, nine hundred fifty-five thousand, four hundred eight".