872639 has 4 divisors (see below), whose sum is σ = 902760. Its totient is φ = 842520.

The previous prime is 872623. The next prime is 872647. The reversal of 872639 is 936278.

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

It is a cyclic number.

It is not a de Polignac number, because 872639 - 2⁴ = 872623 is a prime.

It is a super-4 number, since 4×872639⁴ (a number of 25 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 872599 and 872608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (872609) 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, 15017 + ... + 15074.

It is an arithmetic number, because the mean of its divisors is an integer number (225690).

2⁸⁷²⁶³⁹ is an apocalyptic number.

872639 is a deficient number, since it is larger than the sum of its proper divisors (30121).

872639 is a wasteful number, since it uses less digits than its factorization.

872639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30120.

The product of its digits is 18144, while the sum is 35.

The square root of 872639 is about 934.1514866444. The cubic root of 872639 is about 95.5604543990.

The spelling of 872639 in words is "eight hundred seventy-two thousand, six hundred thirty-nine".