15981157 has 2 divisors, whose sum is σ = 15981158. Its totient is φ = 15981156.

The previous prime is 15981131. The next prime is 15981167. The reversal of 15981157 is 75118951.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12773476 + 3207681 = 3574^2 + 1791^2 .

It is a cyclic number.

It is not a de Polignac number, because 15981157 - 2²³ = 7592549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15981127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7990578 + 7990579.

It is an arithmetic number, because the mean of its divisors is an integer number (7990579).

Almost surely, 2^15981157 is an apocalyptic number.

It is an amenable number.

15981157 is a deficient number, since it is larger than the sum of its proper divisors (1).

15981157 is an equidigital number, since it uses as much as digits as its factorization.

15981157 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12600, while the sum is 37.

The square root of 15981157 is about 3997.6439311174. The cubic root of 15981157 is about 251.8852515700.

The spelling of 15981157 in words is "fifteen million, nine hundred eighty-one thousand, one hundred fifty-seven".