398431031 has 4 divisors (see below), whose sum is σ = 399405600. Its totient is φ = 397456464.

The previous prime is 398431027. The next prime is 398431037. The reversal of 398431031 is 130134893.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 398431031 - 2² = 398431027 is a prime.

It is a super-2 number, since 2×398431031² = 317494572927445922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398431037) 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, 486671 + ... + 487488.

It is an arithmetic number, because the mean of its divisors is an integer number (99851400).

Almost surely, 2^398431031 is an apocalyptic number.

398431031 is a deficient number, since it is larger than the sum of its proper divisors (974569).

398431031 is an equidigital number, since it uses as much as digits as its factorization.

398431031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 974568.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 398431031 is about 19960.7372358838. The cubic root of 398431031 is about 735.8416822114.

The spelling of 398431031 in words is "three hundred ninety-eight million, four hundred thirty-one thousand, thirty-one".