399034991 has 2 divisors, whose sum is σ = 399034992. Its totient is φ = 399034990.

The previous prime is 399034957. The next prime is 399035003. The reversal of 399034991 is 199430993.

It is a strong prime.

It is an emirp because it is prime and its reverse (199430993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 399034991 - 2⁶ = 399034927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (399034091) 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, 199517495 + 199517496.

It is an arithmetic number, because the mean of its divisors is an integer number (199517496).

Almost surely, 2^399034991 is an apocalyptic number.

399034991 is a deficient number, since it is larger than the sum of its proper divisors (1).

399034991 is an equidigital number, since it uses as much as digits as its factorization.

399034991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 236196, while the sum is 47.

The square root of 399034991 is about 19975.8602067596. The cubic root of 399034991 is about 736.2133020066.

The spelling of 399034991 in words is "three hundred ninety-nine million, thirty-four thousand, nine hundred ninety-one".