7989861 has 16 divisors (see below), whose sum is σ = 12234240. Its totient is φ = 4587120.

The previous prime is 7989857. The next prime is 7989869. The reversal of 7989861 is 1689897.

It is a happy number.

It is not a de Polignac number, because 7989861 - 2² = 7989857 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 7989861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7989869) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5745 + ... + 6998.

It is an arithmetic number, because the mean of its divisors is an integer number (764640).

Almost surely, 2^7989861 is an apocalyptic number.

It is an amenable number.

7989861 is a deficient number, since it is larger than the sum of its proper divisors (4244379).

7989861 is a wasteful number, since it uses less digits than its factorization.

7989861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12776.

The product of its digits is 217728, while the sum is 48.

The square root of 7989861 is about 2826.6342175810. The cubic root of 7989861 is about 199.9154726140.

The spelling of 7989861 in words is "seven million, nine hundred eighty-nine thousand, eight hundred sixty-one".