7988689 has 2 divisors, whose sum is σ = 7988690. Its totient is φ = 7988688.

The previous prime is 7988663. The next prime is 7988711. The reversal of 7988689 is 9868897.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4068289 + 3920400 = 2017^2 + 1980^2 .

It is an emirp because it is prime and its reverse (9868897) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7988689 - 2⁹ = 7988177 is a prime.

It is a d-powerful number, because it can be written as 7⁵ + 9² + 8⁷ + 8⁷ + 6⁸ + 8⁷ + 9³ .

It is not a weakly prime, because it can be changed into another prime (7988639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3994344 + 3994345.

It is an arithmetic number, because the mean of its divisors is an integer number (3994345).

Almost surely, 2^7988689 is an apocalyptic number.

It is an amenable number.

7988689 is a deficient number, since it is larger than the sum of its proper divisors (1).

7988689 is an equidigital number, since it uses as much as digits as its factorization.

7988689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1741824, while the sum is 55.

The square root of 7988689 is about 2826.4268962773. The cubic root of 7988689 is about 199.9056972086.

The spelling of 7988689 in words is "seven million, nine hundred eighty-eight thousand, six hundred eighty-nine".