131391 has 12 divisors (see below), whose sum is σ = 204568. Its totient is φ = 80784.

The previous prime is 131381. The next prime is 131413. The reversal of 131391 is 193131.

It is not a de Polignac number, because 131391 - 2¹⁰ = 130367 is a prime.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 131391.

It is not an unprimeable number, because it can be changed into a prime (131311) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 445 + ... + 678.

2¹³¹³⁹¹ is an apocalyptic number.

131391 is a deficient number, since it is larger than the sum of its proper divisors (73177).

131391 is a wasteful number, since it uses less digits than its factorization.

131391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1142 (or 1139 counting only the distinct ones).

The product of its digits is 81, while the sum is 18.

The square root of 131391 is about 362.4789649069. The cubic root of 131391 is about 50.8380096627.

The spelling of 131391 in words is "one hundred thirty-one thousand, three hundred ninety-one".