131097509 has 2 divisors, whose sum is σ = 131097510. Its totient is φ = 131097508.

The previous prime is 131097503. The next prime is 131097517. The reversal of 131097509 is 905790131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124389409 + 6708100 = 11153^2 + 2590^2 .

It is a cyclic number.

It is not a de Polignac number, because 131097509 - 2¹⁶ = 131031973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131097503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65548754 + 65548755.

It is an arithmetic number, because the mean of its divisors is an integer number (65548755).

Almost surely, 2^131097509 is an apocalyptic number.

It is an amenable number.

131097509 is a deficient number, since it is larger than the sum of its proper divisors (1).

131097509 is an equidigital number, since it uses as much as digits as its factorization.

131097509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8505, while the sum is 35.

The square root of 131097509 is about 11449.7820503274. The cubic root of 131097509 is about 508.0012877910.

The spelling of 131097509 in words is "one hundred thirty-one million, ninety-seven thousand, five hundred nine".