123131 has 4 divisors (see below), whose sum is σ = 130392. Its totient is φ = 115872.

The previous prime is 123127. The next prime is 123143. The reversal of 123131 is 131321.

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

It is not a de Polignac number, because 123131 - 2² = 123127 is a prime.

It is a super-2 number, since 2×123131² = 30322486322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3605 + ... + 3638.

It is an arithmetic number, because the mean of its divisors is an integer number (32598).

2¹²³¹³¹ is an apocalyptic number.

123131 is a deficient number, since it is larger than the sum of its proper divisors (7261).

123131 is an equidigital number, since it uses as much as digits as its factorization.

123131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7260.

The product of its digits is 18, while the sum is 11.

The square root of 123131 is about 350.9002707323. The cubic root of 123131 is about 49.7495475662.

Adding to 123131 its reverse (131321), we get a palindrome (254452).

It can be divided in two parts, 1 and 23131, that added together give a palindrome (23132).

The spelling of 123131 in words is "one hundred twenty-three thousand, one hundred thirty-one".