399991900811 has 4 divisors (see below), whose sum is σ = 405471241992. Its totient is φ = 394512559632.

The previous prime is 399991900793. The next prime is 399991900813. The reversal of 399991900811 is 118009199993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 118009199993 = 3137 ⋅37618489.

It is a cyclic number.

It is not a de Polignac number, because 399991900811 - 2¹⁸ = 399991638667 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399991900813) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2739670481 + ... + 2739670626.

It is an arithmetic number, because the mean of its divisors is an integer number (101367810498).

Almost surely, 2^399991900811 is an apocalyptic number.

399991900811 is a deficient number, since it is larger than the sum of its proper divisors (5479341181).

399991900811 is an equidigital number, since it uses as much as digits as its factorization.

399991900811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5479341180.

The product of its (nonzero) digits is 1417176, while the sum is 59.

The spelling of 399991900811 in words is "three hundred ninety-nine billion, nine hundred ninety-one million, nine hundred thousand, eight hundred eleven".