131613409 has 4 divisors (see below), whose sum is σ = 131636416. Its totient is φ = 131590404.

The previous prime is 131613389. The next prime is 131613421. The reversal of 131613409 is 904316131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 904316131 = 41 ⋅22056491.

It is a cyclic number.

It is not a de Polignac number, because 131613409 - 2¹⁵ = 131580641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131613479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4492 + ... + 16834.

It is an arithmetic number, because the mean of its divisors is an integer number (32909104).

Almost surely, 2^131613409 is an apocalyptic number.

It is an amenable number.

131613409 is a deficient number, since it is larger than the sum of its proper divisors (23007).

131613409 is a wasteful number, since it uses less digits than its factorization.

131613409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23006.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 131613409 is about 11472.2887428795. The cubic root of 131613409 is about 508.6667843778. Note that the first 3 decimals are identical.

The spelling of 131613409 in words is "one hundred thirty-one million, six hundred thirteen thousand, four hundred nine".