231186217 has 2 divisors, whose sum is σ = 231186218. Its totient is φ = 231186216.

The previous prime is 231186203. The next prime is 231186227. The reversal of 231186217 is 712681132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 186349801 + 44836416 = 13651^2 + 6696^2 .

It is a cyclic number.

It is not a de Polignac number, because 231186217 - 2⁷ = 231186089 is a prime.

It is not a weakly prime, because it can be changed into another prime (231186227) 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, 115593108 + 115593109.

It is an arithmetic number, because the mean of its divisors is an integer number (115593109).

Almost surely, 2^231186217 is an apocalyptic number.

It is an amenable number.

231186217 is a deficient number, since it is larger than the sum of its proper divisors (1).

231186217 is an equidigital number, since it uses as much as digits as its factorization.

231186217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 31.

The square root of 231186217 is about 15204.8090089945. The cubic root of 231186217 is about 613.7440754195.

The spelling of 231186217 in words is "two hundred thirty-one million, one hundred eighty-six thousand, two hundred seventeen".