231122809 has 2 divisors, whose sum is σ = 231122810. Its totient is φ = 231122808.

The previous prime is 231122789. The next prime is 231122813. The reversal of 231122809 is 908221132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 119355625 + 111767184 = 10925^2 + 10572^2 .

It is a cyclic number.

It is not a de Polignac number, because 231122809 - 2⁵ = 231122777 is a prime.

It is not a weakly prime, because it can be changed into another prime (231122819) 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, 115561404 + 115561405.

It is an arithmetic number, because the mean of its divisors is an integer number (115561405).

Almost surely, 2^231122809 is an apocalyptic number.

It is an amenable number.

231122809 is a deficient number, since it is larger than the sum of its proper divisors (1).

231122809 is an equidigital number, since it uses as much as digits as its factorization.

231122809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 231122809 is about 15202.7237362257. The cubic root of 231122809 is about 613.6879592674.

It can be divided in two parts, 23112 and 2809, that added together give a square (25921 = 161²).

The spelling of 231122809 in words is "two hundred thirty-one million, one hundred twenty-two thousand, eight hundred nine".