21052518706 has 32 divisors (see below), whose sum is σ = 32768472240. Its totient is φ = 10136755200.

The previous prime is 21052518653. The next prime is 21052518713. The reversal of 21052518706 is 60781525012.

It can be written as a sum of positive squares in 8 ways, for example, as 14760063081 + 6292455625 = 121491^2 + 79325^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4938616 + ... + 4942876.

Almost surely, 2^21052518706 is an apocalyptic number.

21052518706 is a deficient number, since it is larger than the sum of its proper divisors (11715953534).

21052518706 is a wasteful number, since it uses less digits than its factorization.

21052518706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5070.

The product of its (nonzero) digits is 33600, while the sum is 37.

The spelling of 21052518706 in words is "twenty-one billion, fifty-two million, five hundred eighteen thousand, seven hundred six".