231220032991 has 2 divisors, whose sum is σ = 231220032992. Its totient is φ = 231220032990.

The previous prime is 231220032983. The next prime is 231220033027. The reversal of 231220032991 is 199230022132.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 231220032991 - 2³ = 231220032983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231220032941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115610016495 + 115610016496.

It is an arithmetic number, because the mean of its divisors is an integer number (115610016496).

Almost surely, 2^231220032991 is an apocalyptic number.

231220032991 is a deficient number, since it is larger than the sum of its proper divisors (1).

231220032991 is an equidigital number, since it uses as much as digits as its factorization.

231220032991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 34.

The spelling of 231220032991 in words is "two hundred thirty-one billion, two hundred twenty million, thirty-two thousand, nine hundred ninety-one".