21316710 has 16 divisors (see below), whose sum is σ = 51160176. Its totient is φ = 5684448.

The previous prime is 21316693. The next prime is 21316721. The reversal of 21316710 is 1761312.

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, 355249 + ... + 355308.

It is an arithmetic number, because the mean of its divisors is an integer number (3197511).

Almost surely, 2^21316710 is an apocalyptic number.

21316710 is an abundant number, since it is smaller than the sum of its proper divisors (29843466).

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

21316710 is a wasteful number, since it uses less digits than its factorization.

21316710 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 710567.

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 21316710 is about 4617.0022742035. The cubic root of 21316710 is about 277.2724536738.

Subtracting from 21316710 its sum of digits (21), we obtain a square (21316689 = 4617²).

The spelling of 21316710 in words is "twenty-one million, three hundred sixteen thousand, seven hundred ten".