21310562516 has 6 divisors (see below), whose sum is σ = 37293484410. Its totient is φ = 10655281256.

The previous prime is 21310562479. The next prime is 21310562563. The reversal of 21310562516 is 61526501312.

It can be written as a sum of positive squares in only one way, i.e., 12855024400 + 8455538116 = 113380^2 + 91954^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2663820311 + ... + 2663820318.

It is an arithmetic number, because the mean of its divisors is an integer number (6215580735).

Almost surely, 2^21310562516 is an apocalyptic number.

It is an amenable number.

21310562516 is a deficient number, since it is larger than the sum of its proper divisors (15982921894).

21310562516 is a wasteful number, since it uses less digits than its factorization.

21310562516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5327640633 (or 5327640631 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 32.

The spelling of 21310562516 in words is "twenty-one billion, three hundred ten million, five hundred sixty-two thousand, five hundred sixteen".