8639989 has 4 divisors (see below), whose sum is σ = 8646156. Its totient is φ = 8633824.

The previous prime is 8639987. The next prime is 8640001. The reversal of 8639989 is 9899368.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 3724900 + 4915089 = 1930^2 + 2217^2 .

It is a cyclic number.

It is not a de Polignac number, because 8639989 - 2¹ = 8639987 is a prime.

It is a Duffinian number.

8639989 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8639987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 147 + ... + 4159.

It is an arithmetic number, because the mean of its divisors is an integer number (2161539).

Almost surely, 2^8639989 is an apocalyptic number.

It is an amenable number.

8639989 is a deficient number, since it is larger than the sum of its proper divisors (6167).

8639989 is a wasteful number, since it uses less digits than its factorization.

8639989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6166.

The product of its digits is 839808, while the sum is 52.

The square root of 8639989 is about 2939.3858202012. The cubic root of 8639989 is about 205.1970265191.

The spelling of 8639989 in words is "eight million, six hundred thirty-nine thousand, nine hundred eighty-nine".