133931 has 12 divisors (see below), whose sum is σ = 164592. Its totient is φ = 106704.

The previous prime is 133919. The next prime is 133949. The reversal of 133931 is 139331.

It is a de Polignac number, because none of the positive numbers 2^k-133931 is a prime.

It is a super-2 number, since 2×133931² = 35875025522, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133981) 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, 2501 + ... + 2553.

It is an arithmetic number, because the mean of its divisors is an integer number (13716).

2¹³³⁹³¹ is an apocalyptic number.

133931 is a deficient number, since it is larger than the sum of its proper divisors (30661).

133931 is an equidigital number, since it uses as much as digits as its factorization.

133931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98 (or 79 counting only the distinct ones).

The product of its digits is 243, while the sum is 20.

The square root of 133931 is about 365.9658454009. The cubic root of 133931 is about 51.1635146560.

The spelling of 133931 in words is "one hundred thirty-three thousand, nine hundred thirty-one".