393968231 has 2 divisors, whose sum is σ = 393968232. Its totient is φ = 393968230.

The previous prime is 393968207. The next prime is 393968233. The reversal of 393968231 is 132869393.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 393968231 - 2⁶ = 393968167 is a prime.

It is a super-2 number, since 2×393968231² = 310421934074538722, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 393968233, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (393968233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 196984115 + 196984116.

It is an arithmetic number, because the mean of its divisors is an integer number (196984116).

Almost surely, 2^393968231 is an apocalyptic number.

393968231 is a deficient number, since it is larger than the sum of its proper divisors (1).

393968231 is an equidigital number, since it uses as much as digits as its factorization.

393968231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 209952, while the sum is 44.

The square root of 393968231 is about 19848.6329755981. The cubic root of 393968231 is about 733.0839886216.

The spelling of 393968231 in words is "three hundred ninety-three million, nine hundred sixty-eight thousand, two hundred thirty-one".