398889923 has 2 divisors, whose sum is σ = 398889924. Its totient is φ = 398889922.

The previous prime is 398889913. The next prime is 398889941. The reversal of 398889923 is 329988893.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 398889923 - 2¹⁰ = 398888899 is a prime.

It is a super-2 number, since 2×398889923² = 318226341341891858, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (398889913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199444961 + 199444962.

It is an arithmetic number, because the mean of its divisors is an integer number (199444962).

Almost surely, 2^398889923 is an apocalyptic number.

398889923 is a deficient number, since it is larger than the sum of its proper divisors (1).

398889923 is an equidigital number, since it uses as much as digits as its factorization.

398889923 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6718464, while the sum is 59.

The square root of 398889923 is about 19972.2287940029. The cubic root of 398889923 is about 736.1240751311.

The spelling of 398889923 in words is "three hundred ninety-eight million, eight hundred eighty-nine thousand, nine hundred twenty-three".