398516815 has 4 divisors (see below), whose sum is σ = 478220184. Its totient is φ = 318813448.

The previous prime is 398516809. The next prime is 398516821. The reversal of 398516815 is 518615893.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 518615893 = 13331 ⋅38903.

It is an interprime number because it is at equal distance from previous prime (398516809) and next prime (398516821).

It is a cyclic number.

It is not a de Polignac number, because 398516815 - 2¹³ = 398508623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39851677 + ... + 39851686.

It is an arithmetic number, because the mean of its divisors is an integer number (119555046).

Almost surely, 2^398516815 is an apocalyptic number.

398516815 is a deficient number, since it is larger than the sum of its proper divisors (79703369).

398516815 is an equidigital number, since it uses as much as digits as its factorization.

398516815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79703368.

The product of its digits is 259200, while the sum is 46.

The square root of 398516815 is about 19962.8859386613. The cubic root of 398516815 is about 735.8944884340.

The spelling of 398516815 in words is "three hundred ninety-eight million, five hundred sixteen thousand, eight hundred fifteen".