131579809 has 2 divisors, whose sum is σ = 131579810. Its totient is φ = 131579808.

The previous prime is 131579771. The next prime is 131579839. The reversal of 131579809 is 908975131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74909025 + 56670784 = 8655^2 + 7528^2 .

It is a cyclic number.

It is not a de Polignac number, because 131579809 - 2⁷ = 131579681 is a prime.

It is a super-2 number, since 2×131579809² = 34626492272952962, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (131579839) 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, 65789904 + 65789905.

It is an arithmetic number, because the mean of its divisors is an integer number (65789905).

Almost surely, 2^131579809 is an apocalyptic number.

It is an amenable number.

131579809 is a deficient number, since it is larger than the sum of its proper divisors (1).

131579809 is an equidigital number, since it uses as much as digits as its factorization.

131579809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 68040, while the sum is 43.

The square root of 131579809 is about 11470.8242511164. The cubic root of 131579809 is about 508.6234943141.

The spelling of 131579809 in words is "one hundred thirty-one million, five hundred seventy-nine thousand, eight hundred nine".