398971916 has 72 divisors (see below), whose sum is σ = 835984800. Its totient is φ = 166053888.

The previous prime is 398971913. The next prime is 398971919. The reversal of 398971916 is 619179893.

It is an interprime number because it is at equal distance from previous prime (398971913) and next prime (398971919).

It is a super-2 number, since 2×398971916² = 318357179513422112, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is not an unprimeable number, because it can be changed into a prime (398971913) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2004785 + ... + 2004983.

It is an arithmetic number, because the mean of its divisors is an integer number (11610900).

Almost surely, 2^398971916 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 398971916, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (417992400).

398971916 is an abundant number, since it is smaller than the sum of its proper divisors (437012884).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

398971916 is a wasteful number, since it uses less digits than its factorization.

398971916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 463 (or 454 counting only the distinct ones).

The product of its digits is 734832, while the sum is 53.

The square root of 398971916 is about 19974.2813637938. The cubic root of 398971916 is about 736.1745091672.

The spelling of 398971916 in words is "three hundred ninety-eight million, nine hundred seventy-one thousand, nine hundred sixteen".