27639989 has 4 divisors (see below), whose sum is σ = 29766156. Its totient is φ = 25513824.

The previous prime is 27639971. The next prime is 27640001. The reversal of 27639989 is 98993672.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4695889 + 22944100 = 2167^2 + 4790^2 .

It is a cyclic number.

It is not a de Polignac number, because 27639989 - 2²⁰ = 26591413 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 27639989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27639949) 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, 1063064 + ... + 1063089.

It is an arithmetic number, because the mean of its divisors is an integer number (7441539).

Almost surely, 2^27639989 is an apocalyptic number.

It is an amenable number.

27639989 is a deficient number, since it is larger than the sum of its proper divisors (2126167).

27639989 is a wasteful number, since it uses less digits than its factorization.

27639989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2126166.

The product of its digits is 1469664, while the sum is 53.

The square root of 27639989 is about 5257.3747250886. The cubic root of 27639989 is about 302.3518442128.

The spelling of 27639989 in words is "twenty-seven million, six hundred thirty-nine thousand, nine hundred eighty-nine".