231405157 has 2 divisors, whose sum is σ = 231405158. Its totient is φ = 231405156.

The previous prime is 231405137. The next prime is 231405179. The reversal of 231405157 is 751504132.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 212751396 + 18653761 = 14586^2 + 4319^2 .

It is a cyclic number.

It is not a de Polignac number, because 231405157 - 2⁷ = 231405029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231405137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115702578 + 115702579.

It is an arithmetic number, because the mean of its divisors is an integer number (115702579).

Almost surely, 2^231405157 is an apocalyptic number.

It is an amenable number.

231405157 is a deficient number, since it is larger than the sum of its proper divisors (1).

231405157 is an equidigital number, since it uses as much as digits as its factorization.

231405157 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 231405157 is about 15212.0070010502. The cubic root of 231405157 is about 613.9377587246.

Adding to 231405157 its reverse (751504132), we get a palindrome (982909289).

The spelling of 231405157 in words is "two hundred thirty-one million, four hundred five thousand, one hundred fifty-seven".