311999231 has 2 divisors, whose sum is σ = 311999232. Its totient is φ = 311999230.

The previous prime is 311999183. The next prime is 311999273. The reversal of 311999231 is 132999113.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 311999231 - 2⁶ = 311999167 is a prime.

It is a super-2 number, since 2×311999231² = 194687040289182722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311999291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155999615 + 155999616.

It is an arithmetic number, because the mean of its divisors is an integer number (155999616).

Almost surely, 2^311999231 is an apocalyptic number.

311999231 is a deficient number, since it is larger than the sum of its proper divisors (1).

311999231 is an equidigital number, since it uses as much as digits as its factorization.

311999231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13122, while the sum is 38.

The square root of 311999231 is about 17663.4999646163. The cubic root of 311999231 is about 678.2417313713.

The spelling of 311999231 in words is "three hundred eleven million, nine hundred ninety-nine thousand, two hundred thirty-one".