231857139 has 16 divisors (see below), whose sum is σ = 316514304. Its totient is φ = 150914400.

The previous prime is 231857113. The next prime is 231857141. The reversal of 231857139 is 931758132.

It is not a de Polignac number, because 231857139 - 2¹⁵ = 231824371 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 231857097 and 231857106.

It is not an unprimeable number, because it can be changed into a prime (231857149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30094 + ... + 37004.

It is an arithmetic number, because the mean of its divisors is an integer number (19782144).

Almost surely, 2^231857139 is an apocalyptic number.

231857139 is a deficient number, since it is larger than the sum of its proper divisors (84657165).

231857139 is a wasteful number, since it uses less digits than its factorization.

231857139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7178.

The product of its digits is 45360, while the sum is 39.

The square root of 231857139 is about 15226.8558474821. The cubic root of 231857139 is about 614.3372144543.

The spelling of 231857139 in words is "two hundred thirty-one million, eight hundred fifty-seven thousand, one hundred thirty-nine".