21455902 has 32 divisors (see below), whose sum is σ = 36842400. Its totient is φ = 9345024.

The previous prime is 21455891. The next prime is 21455927. The reversal of 21455902 is 20955412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83358 + ... + 83614.

It is an arithmetic number, because the mean of its divisors is an integer number (1151325).

Almost surely, 2^21455902 is an apocalyptic number.

21455902 is a deficient number, since it is larger than the sum of its proper divisors (15386498).

21455902 is a wasteful number, since it uses less digits than its factorization.

21455902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317 (or 291 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 28.

The square root of 21455902 is about 4632.0515972947. The cubic root of 21455902 is about 277.8746480394.

The spelling of 21455902 in words is "twenty-one million, four hundred fifty-five thousand, nine hundred two".