624639 has 4 divisors (see below), whose sum is σ = 832856. Its totient is φ = 416424.

The previous prime is 624607. The next prime is 624643. The reversal of 624639 is 936426.

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

It is not a de Polignac number, because 624639 - 2⁵ = 624607 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (624649) 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, 104104 + ... + 104109.

It is an arithmetic number, because the mean of its divisors is an integer number (208214).

2⁶²⁴⁶³⁹ is an apocalyptic number.

624639 is a deficient number, since it is larger than the sum of its proper divisors (208217).

624639 is a wasteful number, since it uses less digits than its factorization.

624639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208216.

The product of its digits is 7776, while the sum is 30.

The square root of 624639 is about 790.3410656166. The cubic root of 624639 is about 85.4823327950.

The spelling of 624639 in words is "six hundred twenty-four thousand, six hundred thirty-nine".