399303913 has 2 divisors, whose sum is σ = 399303914. Its totient is φ = 399303912.

The previous prime is 399303881. The next prime is 399303937. The reversal of 399303913 is 319303993.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 219395344 + 179908569 = 14812^2 + 13413^2 .

It is an emirp because it is prime and its reverse (319303993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 399303913 - 2⁵ = 399303881 is a prime.

It is a super-2 number, since 2×399303913² = 318887229874223138, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (399303013) 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, 199651956 + 199651957.

It is an arithmetic number, because the mean of its divisors is an integer number (199651957).

Almost surely, 2^399303913 is an apocalyptic number.

It is an amenable number.

399303913 is a deficient number, since it is larger than the sum of its proper divisors (1).

399303913 is an equidigital number, since it uses as much as digits as its factorization.

399303913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 59049, while the sum is 40.

The square root of 399303913 is about 19982.5902475130. The cubic root of 399303913 is about 736.3786504922.

The spelling of 399303913 in words is "three hundred ninety-nine million, three hundred three thousand, nine hundred thirteen".