399476813 has 2 divisors, whose sum is σ = 399476814. Its totient is φ = 399476812.

The previous prime is 399476801. The next prime is 399476839. The reversal of 399476813 is 318674993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 304258249 + 95218564 = 17443^2 + 9758^2 .

It is a cyclic number.

It is not a de Polignac number, because 399476813 - 2¹⁰ = 399475789 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (399476873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199738406 + 199738407.

It is an arithmetic number, because the mean of its divisors is an integer number (199738407).

Almost surely, 2^399476813 is an apocalyptic number.

It is an amenable number.

399476813 is a deficient number, since it is larger than the sum of its proper divisors (1).

399476813 is an equidigital number, since it uses as much as digits as its factorization.

399476813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 979776, while the sum is 50.

The square root of 399476813 is about 19986.9160452532. The cubic root of 399476813 is about 736.4849200046.

The spelling of 399476813 in words is "three hundred ninety-nine million, four hundred seventy-six thousand, eight hundred thirteen".