15981131 has 2 divisors, whose sum is σ = 15981132. Its totient is φ = 15981130.

The previous prime is 15981127. The next prime is 15981157. The reversal of 15981131 is 13118951.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 15981131 - 2² = 15981127 is a prime.

It is a super-2 number, since 2×15981131² = 510793096078322, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 15981094 and 15981103.

It is not a weakly prime, because it can be changed into another prime (15981101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7990565 + 7990566.

It is an arithmetic number, because the mean of its divisors is an integer number (7990566).

Almost surely, 2^15981131 is an apocalyptic number.

15981131 is a deficient number, since it is larger than the sum of its proper divisors (1).

15981131 is an equidigital number, since it uses as much as digits as its factorization.

15981131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 29.

The square root of 15981131 is about 3997.6406792007. The cubic root of 15981131 is about 251.8851149712.

The spelling of 15981131 in words is "fifteen million, nine hundred eighty-one thousand, one hundred thirty-one".