231907189 has 2 divisors, whose sum is σ = 231907190. Its totient is φ = 231907188.

The previous prime is 231907163. The next prime is 231907219. The reversal of 231907189 is 981709132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 224011089 + 7896100 = 14967^2 + 2810^2 .

It is a cyclic number.

It is not a de Polignac number, because 231907189 - 2⁷ = 231907061 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231907589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115953594 + 115953595.

It is an arithmetic number, because the mean of its divisors is an integer number (115953595).

Almost surely, 2^231907189 is an apocalyptic number.

It is an amenable number.

231907189 is a deficient number, since it is larger than the sum of its proper divisors (1).

231907189 is an equidigital number, since it uses as much as digits as its factorization.

231907189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27216, while the sum is 40.

The square root of 231907189 is about 15228.4992366287. The cubic root of 231907189 is about 614.3814160483.

The spelling of 231907189 in words is "two hundred thirty-one million, nine hundred seven thousand, one hundred eighty-nine".