131328409 has 2 divisors, whose sum is σ = 131328410. Its totient is φ = 131328408.

The previous prime is 131328391. The next prime is 131328469. The reversal of 131328409 is 904823131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 87834384 + 43494025 = 9372^2 + 6595^2 .

It is a cyclic number.

It is not a de Polignac number, because 131328409 - 2⁵ = 131328377 is a prime.

It is not a weakly prime, because it can be changed into another prime (131328469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65664204 + 65664205.

It is an arithmetic number, because the mean of its divisors is an integer number (65664205).

Almost surely, 2^131328409 is an apocalyptic number.

It is an amenable number.

131328409 is a deficient number, since it is larger than the sum of its proper divisors (1).

131328409 is an equidigital number, since it uses as much as digits as its factorization.

131328409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 131328409 is about 11459.8607757686. The cubic root of 131328409 is about 508.2993577818.

The spelling of 131328409 in words is "one hundred thirty-one million, three hundred twenty-eight thousand, four hundred nine".