86639 has 4 divisors (see below), whose sum is σ = 99024. Its totient is φ = 74256.

The previous prime is 86629. The next prime is 86677. The reversal of 86639 is 93668.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-86639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (86629) 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, 6182 + ... + 6195.

It is an arithmetic number, because the mean of its divisors is an integer number (24756).

2⁸⁶⁶³⁹ is an apocalyptic number.

86639 is a deficient number, since it is larger than the sum of its proper divisors (12385).

86639 is a wasteful number, since it uses less digits than its factorization.

86639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12384.

The product of its digits is 7776, while the sum is 32.

The square root of 86639 is about 294.3450356300. The cubic root of 86639 is about 44.2491035813.

The spelling of 86639 in words is "eighty-six thousand, six hundred thirty-nine".