231033391 has 2 divisors, whose sum is σ = 231033392. Its totient is φ = 231033390.

The previous prime is 231033347. The next prime is 231033419. The reversal of 231033391 is 193330132.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 231033391 - 2¹⁷ = 230902319 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231033301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115516695 + 115516696.

It is an arithmetic number, because the mean of its divisors is an integer number (115516696).

Almost surely, 2^231033391 is an apocalyptic number.

231033391 is a deficient number, since it is larger than the sum of its proper divisors (1).

231033391 is an equidigital number, since it uses as much as digits as its factorization.

231033391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1458, while the sum is 25.

The square root of 231033391 is about 15199.7825971295. The cubic root of 231033391 is about 613.6088067908.

The spelling of 231033391 in words is "two hundred thirty-one million, thirty-three thousand, three hundred ninety-one".