398859431 has 4 divisors (see below), whose sum is σ = 399672264. Its totient is φ = 398046600.

The previous prime is 398859421. The next prime is 398859467. The reversal of 398859431 is 134958893.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 134958893 = 599 ⋅225307.

It is a cyclic number.

It is not a de Polignac number, because 398859431 - 2⁶ = 398859367 is a prime.

It is a super-2 number, since 2×398859431² = 318177691395287522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 398859431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398859401) 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, 405680 + ... + 406661.

It is an arithmetic number, because the mean of its divisors is an integer number (99918066).

Almost surely, 2^398859431 is an apocalyptic number.

398859431 is a deficient number, since it is larger than the sum of its proper divisors (812833).

398859431 is an equidigital number, since it uses as much as digits as its factorization.

398859431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812832.

The product of its digits is 933120, while the sum is 50.

The square root of 398859431 is about 19971.4654194428. The cubic root of 398859431 is about 736.1053176862.

The spelling of 398859431 in words is "three hundred ninety-eight million, eight hundred fifty-nine thousand, four hundred thirty-one".