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231881 = 1317837
BaseRepresentation
bin111000100111001001
3102210002012
4320213021
524410011
64545305
71654016
oct704711
9383065
10231881
11149241
12b2235
1381710
146070d
1548a8b
hex389c9

231881 has 4 divisors (see below), whose sum is σ = 249732. Its totient is φ = 214032.

The previous prime is 231877. The next prime is 231893. The reversal of 231881 is 188132.

231881 = 3402 + 3412.

231881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 116281 + 115600 = 341^2 + 340^2 .

It is not a de Polignac number, because 231881 - 22 = 231877 is a prime.

It is a super-2 number, since 2×2318812 = 107537596322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (231821) 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, 8906 + ... + 8931.

It is an arithmetic number, because the mean of its divisors is an integer number (62433).

2231881 is an apocalyptic number.

231881 is the 341-st centered square number.

It is an amenable number.

231881 is a deficient number, since it is larger than the sum of its proper divisors (17851).

231881 is a wasteful number, since it uses less digits than its factorization.

231881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17850.

The product of its digits is 384, while the sum is 23.

The square root of 231881 is about 481.5402371557. The cubic root of 231881 is about 61.4358288060.

The spelling of 231881 in words is "two hundred thirty-one thousand, eight hundred eighty-one".

Divisors: 1 13 17837 231881