398831191 has 4 divisors (see below), whose sum is σ = 435088584. Its totient is φ = 362573800.

The previous prime is 398831189. The next prime is 398831221. The reversal of 398831191 is 191138893.

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 398831191 - 2¹ = 398831189 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 (398831291) 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, 18128680 + ... + 18128701.

It is an arithmetic number, because the mean of its divisors is an integer number (108772146).

Almost surely, 2^398831191 is an apocalyptic number.

398831191 is a deficient number, since it is larger than the sum of its proper divisors (36257393).

398831191 is a wasteful number, since it uses less digits than its factorization.

398831191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36257392.

The product of its digits is 46656, while the sum is 43.

The square root of 398831191 is about 19970.7583982181. The cubic root of 398831191 is about 736.0879447279.

The spelling of 398831191 in words is "three hundred ninety-eight million, eight hundred thirty-one thousand, one hundred ninety-one".