789639 has 4 divisors (see below), whose sum is σ = 1052856. Its totient is φ = 526424.

The previous prime is 789631. The next prime is 789653. The reversal of 789639 is 936987.

It is a happy number.

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 789639 - 2³ = 789631 is a prime.

It is a D-number.

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 789639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (789631) 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, 131604 + ... + 131609.

It is an arithmetic number, because the mean of its divisors is an integer number (263214).

2⁷⁸⁹⁶³⁹ is an apocalyptic number.

789639 is a deficient number, since it is larger than the sum of its proper divisors (263217).

789639 is a wasteful number, since it uses less digits than its factorization.

789639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263216.

The product of its digits is 81648, while the sum is 42.

The square root of 789639 is about 888.6163401604. The cubic root of 789639 is about 92.4292714742.

The spelling of 789639 in words is "seven hundred eighty-nine thousand, six hundred thirty-nine".