215945231 has 2 divisors, whose sum is σ = 215945232. Its totient is φ = 215945230.

The previous prime is 215945227. The next prime is 215945243. The reversal of 215945231 is 132549512.

215945231 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 215945231 - 2² = 215945227 is a prime.

It is a super-2 number, since 2×215945231² = 93264685583286722, which contains 22 as substring.

It is a Chen prime.

It is equal to p_11911496 and since 215945231 and 11911496 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215945201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107972615 + 107972616.

It is an arithmetic number, because the mean of its divisors is an integer number (107972616).

Almost surely, 2^215945231 is an apocalyptic number.

215945231 is a deficient number, since it is larger than the sum of its proper divisors (1).

215945231 is an equidigital number, since it uses as much as digits as its factorization.

215945231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10800, while the sum is 32.

The square root of 215945231 is about 14695.0750593524. The cubic root of 215945231 is about 599.9492836762.

The spelling of 215945231 in words is "two hundred fifteen million, nine hundred forty-five thousand, two hundred thirty-one".