391888980 has 288 divisors, whose sum is σ = 1431306240. Its totient is φ = 84913920.

The previous prime is 391888979. The next prime is 391888999. The reversal of 391888980 is 89888193.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3085677 + ... + 3085803.

Almost surely, 2^391888980 is an apocalyptic number.

391888980 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 391888980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (715653120).

391888980 is an abundant number, since it is smaller than the sum of its proper divisors (1039417260).

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

391888980 is a wasteful number, since it uses less digits than its factorization.

391888980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259 (or 254 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 54.

The square root of 391888980 is about 19796.1859962974. The cubic root of 391888980 is about 731.7920443042.

It can be divided in two parts, 3 and 91888980, that multiplied together give a triangular number (275666940 = T₂₃₄₈₀).

The spelling of 391888980 in words is "three hundred ninety-one million, eight hundred eighty-eight thousand, nine hundred eighty".