231781508123 has 4 divisors (see below), whose sum is σ = 252852554328. Its totient is φ = 210710461920.

The previous prime is 231781508107. The next prime is 231781508131. The reversal of 231781508123 is 321805187132.

231781508123 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 231781508123 - 2⁴ = 231781508107 is a prime.

It is not an unprimeable number, because it can be changed into a prime (231781508323) 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 3 ways as a sum of consecutive naturals, for example, 10535523086 + ... + 10535523107.

It is an arithmetic number, because the mean of its divisors is an integer number (63213138582).

Almost surely, 2^231781508123 is an apocalyptic number.

231781508123 is a deficient number, since it is larger than the sum of its proper divisors (21071046205).

231781508123 is a wasteful number, since it uses less digits than its factorization.

231781508123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21071046204.

The product of its (nonzero) digits is 80640, while the sum is 41.

The spelling of 231781508123 in words is "two hundred thirty-one billion, seven hundred eighty-one million, five hundred eight thousand, one hundred twenty-three".