131256691 has 2 divisors, whose sum is σ = 131256692. Its totient is φ = 131256690.

The previous prime is 131256679. The next prime is 131256707. The reversal of 131256691 is 196652131.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 131256691 - 2⁷ = 131256563 is a prime.

It is not a weakly prime, because it can be changed into another prime (131256611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65628345 + 65628346.

It is an arithmetic number, because the mean of its divisors is an integer number (65628346).

Almost surely, 2^131256691 is an apocalyptic number.

131256691 is a deficient number, since it is larger than the sum of its proper divisors (1).

131256691 is an equidigital number, since it uses as much as digits as its factorization.

131256691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9720, while the sum is 34.

The square root of 131256691 is about 11456.7312528487. The cubic root of 131256691 is about 508.2068140804.

The spelling of 131256691 in words is "one hundred thirty-one million, two hundred fifty-six thousand, six hundred ninety-one".