398830851691 has 2 divisors, whose sum is σ = 398830851692. Its totient is φ = 398830851690.

The previous prime is 398830851611. The next prime is 398830851697. The reversal of 398830851691 is 196158038893.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 398830851691 - 2²⁵ = 398797297259 is a prime.

It is not a weakly prime, because it can be changed into another prime (398830851697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199415425845 + 199415425846.

It is an arithmetic number, because the mean of its divisors is an integer number (199415425846).

Almost surely, 2^398830851691 is an apocalyptic number.

398830851691 is a deficient number, since it is larger than the sum of its proper divisors (1).

398830851691 is an equidigital number, since it uses as much as digits as its factorization.

398830851691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11197440, while the sum is 61.

It can be divided in two parts, 398830 and 851691, that added together give a palindrome (1250521).

The spelling of 398830851691 in words is "three hundred ninety-eight billion, eight hundred thirty million, eight hundred fifty-one thousand, six hundred ninety-one".