187431913 has 2 divisors, whose sum is σ = 187431914. Its totient is φ = 187431912.

The previous prime is 187431863. The next prime is 187431917. The reversal of 187431913 is 319134781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 161493264 + 25938649 = 12708^2 + 5093^2 .

It is a cyclic number.

It is not a de Polignac number, because 187431913 - 2⁹ = 187431401 is a prime.

It is not a weakly prime, because it can be changed into another prime (187431917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93715956 + 93715957.

It is an arithmetic number, because the mean of its divisors is an integer number (93715957).

Almost surely, 2^187431913 is an apocalyptic number.

It is an amenable number.

187431913 is a deficient number, since it is larger than the sum of its proper divisors (1).

187431913 is an equidigital number, since it uses as much as digits as its factorization.

187431913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 37.

The square root of 187431913 is about 13690.5775261674. The cubic root of 187431913 is about 572.2878327481.

The spelling of 187431913 in words is "one hundred eighty-seven million, four hundred thirty-one thousand, nine hundred thirteen".