231113209991 has 2 divisors, whose sum is σ = 231113209992. Its totient is φ = 231113209990.

The previous prime is 231113209963. The next prime is 231113210063. The reversal of 231113209991 is 199902311132.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 231113209991 - 2²⁶ = 231046101127 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231113209291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115556604995 + 115556604996.

It is an arithmetic number, because the mean of its divisors is an integer number (115556604996).

Almost surely, 2^231113209991 is an apocalyptic number.

231113209991 is a deficient number, since it is larger than the sum of its proper divisors (1).

231113209991 is an equidigital number, since it uses as much as digits as its factorization.

231113209991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26244, while the sum is 41.

The spelling of 231113209991 in words is "two hundred thirty-one billion, one hundred thirteen million, two hundred nine thousand, nine hundred ninety-one".