15939972 has 18 divisors (see below), whose sum is σ = 40292798. Its totient is φ = 5313312.

The previous prime is 15939961. The next prime is 15940009. The reversal of 15939972 is 27993951.

It is a happy number.

15939972 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 10850436 + 5089536 = 3294^2 + 2256^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 221353 + ... + 221424.

Almost surely, 2^15939972 is an apocalyptic number.

15939972 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

15939972 is an abundant number, since it is smaller than the sum of its proper divisors (24352826).

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

15939972 is a wasteful number, since it uses less digits than its factorization.

15939972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 442787 (or 442782 counting only the distinct ones).

The product of its digits is 153090, while the sum is 45.

The square root of 15939972 is about 3992.4894489529. The cubic root of 15939972 is about 251.6686878094.

The spelling of 15939972 in words is "fifteen million, nine hundred thirty-nine thousand, nine hundred seventy-two".