15131997 has 12 divisors (see below), whose sum is σ = 22611420. Its totient is φ = 9739968.

The previous prime is 15131983. The next prime is 15132031. The reversal of 15131997 is 79913151.

It can be written as a sum of positive squares in 2 ways, for example, as 6095961 + 9036036 = 2469^2 + 3006^2 .

It is not a de Polignac number, because 15131997 - 2⁴ = 15131981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15131917) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28728 + ... + 29249.

It is an arithmetic number, because the mean of its divisors is an integer number (1884285).

Almost surely, 2^15131997 is an apocalyptic number.

It is an amenable number.

15131997 is a deficient number, since it is larger than the sum of its proper divisors (7479423).

15131997 is a wasteful number, since it uses less digits than its factorization.

15131997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58012 (or 58009 counting only the distinct ones).

The product of its digits is 8505, while the sum is 36.

The square root of 15131997 is about 3889.9867609029. The cubic root of 15131997 is about 247.3425015713.

The spelling of 15131997 in words is "fifteen million, one hundred thirty-one thousand, nine hundred ninety-seven".