7989891 has 48 divisors (see below), whose sum is σ = 13827744. Its totient is φ = 4064256.

The previous prime is 7989869. The next prime is 7989907. The reversal of 7989891 is 1989897.

It is not a de Polignac number, because 7989891 - 2¹¹ = 7987843 is a prime.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (7989851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 70651 + ... + 70763.

It is an arithmetic number, because the mean of its divisors is an integer number (288078).

Almost surely, 2^7989891 is an apocalyptic number.

7989891 is a deficient number, since it is larger than the sum of its proper divisors (5837853).

7989891 is a wasteful number, since it uses less digits than its factorization.

7989891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180 (or 173 counting only the distinct ones).

The product of its digits is 326592, while the sum is 51.

The square root of 7989891 is about 2826.6395242408. The cubic root of 7989891 is about 199.9157228251.

The spelling of 7989891 in words is "seven million, nine hundred eighty-nine thousand, eight hundred ninety-one".