7991880 has 128 divisors (see below), whose sum is σ = 26611200. Its totient is φ = 1907712.

The previous prime is 7991869. The next prime is 7991891. The reversal of 7991880 is 881997.

7991880 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (7991869) and next prime (7991891).

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 73266 + ... + 73374.

It is an arithmetic number, because the mean of its divisors is an integer number (207900).

Almost surely, 2^7991880 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 7991880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13305600).

7991880 is an abundant number, since it is smaller than the sum of its proper divisors (18619320).

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

7991880 is a wasteful number, since it uses less digits than its factorization.

7991880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183 (or 179 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 42.

The square root of 7991880 is about 2826.9913335559. The cubic root of 7991880 is about 199.9323104265.

The spelling of 7991880 in words is "seven million, nine hundred ninety-one thousand, eight hundred eighty".