398636880 has 80 divisors (see below), whose sum is σ = 1246795200. Its totient is φ = 105355264.

The previous prime is 398636879. The next prime is 398636921. The reversal of 398636880 is 88636893.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×398636880² = 317822724192268800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19771 + ... + 34469.

It is an arithmetic number, because the mean of its divisors is an integer number (15584940).

Almost surely, 2^398636880 is an apocalyptic number.

398636880 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 398636880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (623397600).

398636880 is an abundant number, since it is smaller than the sum of its proper divisors (848158320).

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

398636880 is a wasteful number, since it uses less digits than its factorization.

398636880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14828 (or 14822 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 51.

The square root of 398636880 is about 19965.8929176734. The cubic root of 398636880 is about 735.9683843540.

The spelling of 398636880 in words is "three hundred ninety-eight million, six hundred thirty-six thousand, eight hundred eighty".