398438917 has 8 divisors (see below), whose sum is σ = 416183040. Its totient is φ = 380961840.

The previous prime is 398438899. The next prime is 398438947. The reversal of 398438917 is 719834893.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 398438917 - 2²⁷ = 264221189 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 (398438947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63709 + ... + 69682.

It is an arithmetic number, because the mean of its divisors is an integer number (52022880).

Almost surely, 2^398438917 is an apocalyptic number.

It is an amenable number.

398438917 is a deficient number, since it is larger than the sum of its proper divisors (17744123).

398438917 is a wasteful number, since it uses less digits than its factorization.

398438917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133523.

The product of its digits is 1306368, while the sum is 52.

The square root of 398438917 is about 19960.9347727004. The cubic root of 398438917 is about 735.8465369280.

The spelling of 398438917 in words is "three hundred ninety-eight million, four hundred thirty-eight thousand, nine hundred seventeen".