399499361 has 2 divisors, whose sum is σ = 399499362. Its totient is φ = 399499360.

The previous prime is 399499357. The next prime is 399499363. The reversal of 399499361 is 163994993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 366952336 + 32547025 = 19156^2 + 5705^2 .

It is an emirp because it is prime and its reverse (163994993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 399499361 - 2² = 399499357 is a prime.

It is a super-4 number, since 4×399499361⁴ (a number of 36 digits) contains 4444 as substring.

Together with 399499363, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (399499363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199749680 + 199749681.

It is an arithmetic number, because the mean of its divisors is an integer number (199749681).

Almost surely, 2^399499361 is an apocalyptic number.

It is an amenable number.

399499361 is a deficient number, since it is larger than the sum of its proper divisors (1).

399499361 is an equidigital number, since it uses as much as digits as its factorization.

399499361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1417176, while the sum is 53.

The square root of 399499361 is about 19987.4801063065. The cubic root of 399499361 is about 736.4987764197.

The spelling of 399499361 in words is "three hundred ninety-nine million, four hundred ninety-nine thousand, three hundred sixty-one".