231402217 has 2 divisors, whose sum is σ = 231402218. Its totient is φ = 231402216.

The previous prime is 231402209. The next prime is 231402233. The reversal of 231402217 is 712204132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 210279001 + 21123216 = 14501^2 + 4596^2 .

It is a cyclic number.

It is not a de Polignac number, because 231402217 - 2³ = 231402209 is a prime.

It is not a weakly prime, because it can be changed into another prime (231402617) 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, 115701108 + 115701109.

It is an arithmetic number, because the mean of its divisors is an integer number (115701109).

Almost surely, 2^231402217 is an apocalyptic number.

It is an amenable number.

231402217 is a deficient number, since it is larger than the sum of its proper divisors (1).

231402217 is an equidigital number, since it uses as much as digits as its factorization.

231402217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 231402217 is about 15211.9103665516. The cubic root of 231402217 is about 613.9351586894.

Adding to 231402217 its reverse (712204132), we get a palindrome (943606349).

The spelling of 231402217 in words is "two hundred thirty-one million, four hundred two thousand, two hundred seventeen".