21382808 has 32 divisors (see below), whose sum is σ = 41733120. Its totient is φ = 10260000.

The previous prime is 21382799. The next prime is 21382813. The reversal of 21382808 is 80828312.

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, 37163 + ... + 37733.

It is an arithmetic number, because the mean of its divisors is an integer number (1304160).

Almost surely, 2^21382808 is an apocalyptic number.

It is an amenable number.

21382808 is a deficient number, since it is larger than the sum of its proper divisors (20350312).

21382808 is a wasteful number, since it uses less digits than its factorization.

21382808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 759 (or 755 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 32.

The square root of 21382808 is about 4624.1548416981. The cubic root of 21382808 is about 277.5587430763.

The spelling of 21382808 in words is "twenty-one million, three hundred eighty-two thousand, eight hundred eight".