131195509 has 2 divisors, whose sum is σ = 131195510. Its totient is φ = 131195508.

The previous prime is 131195489. The next prime is 131195539. The reversal of 131195509 is 905591131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 118875409 + 12320100 = 10903^2 + 3510^2 .

It is a cyclic number.

It is not a de Polignac number, because 131195509 - 2⁹ = 131194997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131195539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65597754 + 65597755.

It is an arithmetic number, because the mean of its divisors is an integer number (65597755).

Almost surely, 2^131195509 is an apocalyptic number.

It is an amenable number.

131195509 is a deficient number, since it is larger than the sum of its proper divisors (1).

131195509 is an equidigital number, since it uses as much as digits as its factorization.

131195509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6075, while the sum is 34.

The square root of 131195509 is about 11454.0608082898. The cubic root of 131195509 is about 508.1278392071.

The spelling of 131195509 in words is "one hundred thirty-one million, one hundred ninety-five thousand, five hundred nine".