131609571791 has 4 divisors (see below), whose sum is σ = 131824269912. Its totient is φ = 131394873672.

The previous prime is 131609571749. The next prime is 131609571817. The reversal of 131609571791 is 197175906131.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 131609571791 - 2¹⁸ = 131609309647 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131609571091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107348141 + ... + 107349366.

It is an arithmetic number, because the mean of its divisors is an integer number (32956067478).

Almost surely, 2^131609571791 is an apocalyptic number.

131609571791 is a deficient number, since it is larger than the sum of its proper divisors (214698121).

131609571791 is an equidigital number, since it uses as much as digits as its factorization.

131609571791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214698120.

The product of its (nonzero) digits is 357210, while the sum is 50.

The spelling of 131609571791 in words is "one hundred thirty-one billion, six hundred nine million, five hundred seventy-one thousand, seven hundred ninety-one".