398137181 has 4 divisors (see below), whose sum is σ = 428763132. Its totient is φ = 367511232.

The previous prime is 398137171. The next prime is 398137189. The reversal of 398137181 is 181731893.

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

It can be written as a sum of positive squares in 2 ways, for example, as 78943225 + 319193956 = 8885^2 + 17866^2 .

It is a cyclic number.

It is not a de Polignac number, because 398137181 - 2²² = 393942877 is a prime.

It is a super-2 number, since 2×398137181² = 317026429789253522, 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 (398137189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15312956 + ... + 15312981.

It is an arithmetic number, because the mean of its divisors is an integer number (107190783).

Almost surely, 2^398137181 is an apocalyptic number.

It is an amenable number.

398137181 is a deficient number, since it is larger than the sum of its proper divisors (30625951).

398137181 is a wasteful number, since it uses less digits than its factorization.

398137181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30625950.

The product of its digits is 36288, while the sum is 41.

The square root of 398137181 is about 19953.3751781497. The cubic root of 398137181 is about 735.6607389277.

The spelling of 398137181 in words is "three hundred ninety-eight million, one hundred thirty-seven thousand, one hundred eighty-one".