117831 has 16 divisors (see below), whose sum is σ = 186368. Its totient is φ = 64800.

The previous prime is 117811. The next prime is 117833. The reversal of 117831 is 138711.

117831 = T₂₈ + T₂₉ + ... + T₈₉.

117831 = 46² + 47² + ... + 76².

It is not a de Polignac number, because 117831 - 2⁷ = 117703 is a prime.

It is a super-2 number, since 2×117831² = 27768289122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 117798 and 117807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (117833) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 561 + ... + 741.

It is an arithmetic number, because the mean of its divisors is an integer number (11648).

2¹¹⁷⁸³¹ is an apocalyptic number.

117831 is a deficient number, since it is larger than the sum of its proper divisors (68537).

117831 is a wasteful number, since it uses less digits than its factorization.

117831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222.

The product of its digits is 168, while the sum is 21.

The square root of 117831 is about 343.2652035963. The cubic root of 117831 is about 49.0252542317.

The spelling of 117831 in words is "one hundred seventeen thousand, eight hundred thirty-one".