399990010992809 has 2 divisors, whose sum is σ = 399990010992810. Its totient is φ = 399990010992808.

The previous prime is 399990010992763. The next prime is 399990010992899. The reversal of 399990010992809 is 908299010099993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 208273531939225 + 191716479053584 = 14431685^2 + 13846172^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-399990010992809 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 399990010992809.

It is not a weakly prime, because it can be changed into another prime (399990010992899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199995005496404 + 199995005496405.

It is an arithmetic number, because the mean of its divisors is an integer number (199995005496405).

Almost surely, 2^{399990010992809} is an apocalyptic number.

It is an amenable number.

399990010992809 is a deficient number, since it is larger than the sum of its proper divisors (1).

399990010992809 is an equidigital number, since it uses as much as digits as its factorization.

399990010992809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 229582512, while the sum is 77.

The spelling of 399990010992809 in words is "three hundred ninety-nine trillion, nine hundred ninety billion, ten million, nine hundred ninety-two thousand, eight hundred nine".