231505123 has 2 divisors, whose sum is σ = 231505124. Its totient is φ = 231505122.

The previous prime is 231505111. The next prime is 231505159. The reversal of 231505123 is 321505132.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 231505123 - 2⁵ = 231505091 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 231505094 and 231505103.

It is not a weakly prime, because it can be changed into another prime (231505103) 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, 115752561 + 115752562.

It is an arithmetic number, because the mean of its divisors is an integer number (115752562).

Almost surely, 2^231505123 is an apocalyptic number.

231505123 is a deficient number, since it is larger than the sum of its proper divisors (1).

231505123 is an equidigital number, since it uses as much as digits as its factorization.

231505123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 231505123 is about 15215.2924059973. The cubic root of 231505123 is about 614.0261521256.

Subtracting 231505123 from its reverse (321505132), we obtain a palindrome (90000009).

The spelling of 231505123 in words is "two hundred thirty-one million, five hundred five thousand, one hundred twenty-three".