399245766893 has 2 divisors, whose sum is σ = 399245766894. Its totient is φ = 399245766892.

The previous prime is 399245766811. The next prime is 399245766943. The reversal of 399245766893 is 398667542993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 302458201444 + 96787565449 = 549962^2 + 311107^2 .

It is a cyclic number.

It is not a de Polignac number, because 399245766893 - 2²⁸ = 398977331437 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (399245766193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199622883446 + 199622883447.

It is an arithmetic number, because the mean of its divisors is an integer number (199622883447).

Almost surely, 2^399245766893 is an apocalyptic number.

It is an amenable number.

399245766893 is a deficient number, since it is larger than the sum of its proper divisors (1).

399245766893 is an equidigital number, since it uses as much as digits as its factorization.

399245766893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 529079040, while the sum is 71.

The spelling of 399245766893 in words is "three hundred ninety-nine billion, two hundred forty-five million, seven hundred sixty-six thousand, eight hundred ninety-three".