21056610 has 32 divisors (see below), whose sum is σ = 52280640. Its totient is φ = 5421248.

The previous prime is 21056597. The next prime is 21056653. The reversal of 21056610 is 1665012.

It is a happy 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, 11232 + ... + 12971.

It is an arithmetic number, because the mean of its divisors is an integer number (1633770).

Almost surely, 2^21056610 is an apocalyptic number.

21056610 is an abundant number, since it is smaller than the sum of its proper divisors (31224030).

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

21056610 is a wasteful number, since it uses less digits than its factorization.

21056610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24242.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 21056610 is about 4588.7481953143. The cubic root of 21056610 is about 276.1401042510.

The spelling of 21056610 in words is "twenty-one million, fifty-six thousand, six hundred ten".