21913404 has 24 divisors (see below), whose sum is σ = 52781568. Its totient is φ = 7068720.

The previous prime is 21913399. The next prime is 21913427. The reversal of 21913404 is 40431912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29082 + ... + 29825.

It is an arithmetic number, because the mean of its divisors is an integer number (2199232).

Almost surely, 2^21913404 is an apocalyptic number.

It is an amenable number.

21913404 is an abundant number, since it is smaller than the sum of its proper divisors (30868164).

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

21913404 is a wasteful number, since it uses less digits than its factorization.

21913404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58945 (or 58943 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 21913404 is about 4681.1754933991. The cubic root of 21913404 is about 279.8358050938.

The spelling of 21913404 in words is "twenty-one million, nine hundred thirteen thousand, four hundred four".