398131491 has 16 divisors (see below), whose sum is σ = 560419200. Its totient is φ = 250714368.

The previous prime is 398131457. The next prime is 398131493. The reversal of 398131491 is 194131893.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-398131491 is a prime.

It is not an unprimeable number, because it can be changed into a prime (398131493) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9715 + ... + 29843.

It is an arithmetic number, because the mean of its divisors is an integer number (35026200).

Almost surely, 2^398131491 is an apocalyptic number.

398131491 is a deficient number, since it is larger than the sum of its proper divisors (162287709).

398131491 is a wasteful number, since it uses less digits than its factorization.

398131491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20498.

The product of its digits is 23328, while the sum is 39.

The square root of 398131491 is about 19953.2325952463. The cubic root of 398131491 is about 735.6572343320.

The spelling of 398131491 in words is "three hundred ninety-eight million, one hundred thirty-one thousand, four hundred ninety-one".