87639289 has 4 divisors (see below), whose sum is σ = 89677456. Its totient is φ = 85601124.

The previous prime is 87639281. The next prime is 87639323. The reversal of 87639289 is 98293678.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 87639289 - 2³ = 87639281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87639281) 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, 1019019 + ... + 1019104.

It is an arithmetic number, because the mean of its divisors is an integer number (22419364).

Almost surely, 2^87639289 is an apocalyptic number.

It is an amenable number.

87639289 is a deficient number, since it is larger than the sum of its proper divisors (2038167).

87639289 is a wasteful number, since it uses less digits than its factorization.

87639289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2038166.

The product of its digits is 1306368, while the sum is 52.

The square root of 87639289 is about 9361.5858165163. The cubic root of 87639289 is about 444.1874479062.

The spelling of 87639289 in words is "eighty-seven million, six hundred thirty-nine thousand, two hundred eighty-nine".