15664531444 has 12 divisors (see below), whose sum is σ = 27414015300. Its totient is φ = 7831955648.

The previous prime is 15664531439. The next prime is 15664531457. The reversal of 15664531444 is 44413546651.

It can be written as a sum of positive squares in 2 ways, for example, as 7754563600 + 7909967844 = 88060^2 + 88938^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 15664531444.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65442 + ... + 188710.

It is an arithmetic number, because the mean of its divisors is an integer number (2284501275).

Almost surely, 2^15664531444 is an apocalyptic number.

It is an amenable number.

15664531444 is a deficient number, since it is larger than the sum of its proper divisors (11749483856).

15664531444 is a wasteful number, since it uses less digits than its factorization.

15664531444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155042 (or 155040 counting only the distinct ones).

The product of its digits is 691200, while the sum is 43.

The spelling of 15664531444 in words is "fifteen billion, six hundred sixty-four million, five hundred thirty-one thousand, four hundred forty-four".