21655802 has 16 divisors (see below), whose sum is σ = 37184640. Its totient is φ = 9265968.

The previous prime is 21655787. The next prime is 21655813. The reversal of 21655802 is 20855612.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14243 + ... + 15689.

It is an arithmetic number, because the mean of its divisors is an integer number (2324040).

Almost surely, 2^21655802 is an apocalyptic number.

21655802 is a deficient number, since it is larger than the sum of its proper divisors (15528838).

21655802 is a wasteful number, since it uses less digits than its factorization.

21655802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2525.

The product of its (nonzero) digits is 4800, while the sum is 29.

The square root of 21655802 is about 4653.5794825059. The cubic root of 21655802 is about 278.7349478087.

The spelling of 21655802 in words is "twenty-one million, six hundred fifty-five thousand, eight hundred two".