21104008 has 16 divisors (see below), whose sum is σ = 40113180. Its totient is φ = 10407168.

The previous prime is 21103961. The next prime is 21104011. The reversal of 21104008 is 80040112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20958084 + 145924 = 4578^2 + 382^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21103982 and 21104000.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17485 + ... + 18652.

Almost surely, 2^21104008 is an apocalyptic number.

It is an amenable number.

21104008 is a deficient number, since it is larger than the sum of its proper divisors (19009172).

21104008 is a wasteful number, since it uses less digits than its factorization.

21104008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36216 (or 36212 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 21104008 is about 4593.9098815715. The cubic root of 21104008 is about 276.3471442301.

The spelling of 21104008 in words is "twenty-one million, one hundred four thousand, eight".