15664645525 has 12 divisors (see below), whose sum is σ = 19897921764. Its totient is φ = 12226064000.

The previous prime is 15664645471. The next prime is 15664645567. The reversal of 15664645525 is 52554646651.

It can be written as a sum of positive squares in 6 ways, for example, as 212663889 + 15451981636 = 14583^2 + 124306^2 .

It is not a de Polignac number, because 15664645525 - 2¹³ = 15664637333 is a prime.

It is a super-2 number, since 2×15664645525² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 7640266 + ... + 7642315.

It is an arithmetic number, because the mean of its divisors is an integer number (1658160147).

Almost surely, 2^15664645525 is an apocalyptic number.

It is an amenable number.

15664645525 is a deficient number, since it is larger than the sum of its proper divisors (4233276239).

15664645525 is a wasteful number, since it uses less digits than its factorization.

15664645525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15282632 (or 15282627 counting only the distinct ones).

The product of its digits is 4320000, while the sum is 49.

The spelling of 15664645525 in words is "fifteen billion, six hundred sixty-four million, six hundred forty-five thousand, five hundred twenty-five".