398389999 has 4 divisors (see below), whose sum is σ = 455302864. Its totient is φ = 341477136.

The previous prime is 398389939. The next prime is 398390011. The reversal of 398389999 is 999983893.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 398389999 - 2²¹ = 396292847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398389919) 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, 28456422 + ... + 28456435.

It is an arithmetic number, because the mean of its divisors is an integer number (113825716).

Almost surely, 2^398389999 is an apocalyptic number.

398389999 is a deficient number, since it is larger than the sum of its proper divisors (56912865).

398389999 is an equidigital number, since it uses as much as digits as its factorization.

398389999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56912864.

The product of its digits is 34012224, while the sum is 67.

The square root of 398389999 is about 19959.7093916720. The cubic root of 398389999 is about 735.8164213840.

The spelling of 398389999 in words is "three hundred ninety-eight million, three hundred eighty-nine thousand, nine hundred ninety-nine".