131508809 has 2 divisors, whose sum is σ = 131508810. Its totient is φ = 131508808.

The previous prime is 131508799. The next prime is 131508833. The reversal of 131508809 is 908805131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 130873600 + 635209 = 11440^2 + 797^2 .

It is a cyclic number.

It is not a de Polignac number, because 131508809 - 2²⁴ = 114731593 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (131502809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65754404 + 65754405.

It is an arithmetic number, because the mean of its divisors is an integer number (65754405).

Almost surely, 2^131508809 is an apocalyptic number.

It is an amenable number.

131508809 is a deficient number, since it is larger than the sum of its proper divisors (1).

131508809 is an equidigital number, since it uses as much as digits as its factorization.

131508809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 35.

The square root of 131508809 is about 11467.7290253999. The cubic root of 131508809 is about 508.5319940409.

The spelling of 131508809 in words is "one hundred thirty-one million, five hundred eight thousand, eight hundred nine".