618639 has 16 divisors (see below), whose sum is σ = 956160. Its totient is φ = 348480.

The previous prime is 618637. The next prime is 618643. The reversal of 618639 is 936816.

618639 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 618639 - 2¹ = 618637 is a prime.

618639 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (618637) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1704 + ... + 2034.

It is an arithmetic number, because the mean of its divisors is an integer number (59760).

2⁶¹⁸⁶³⁹ is an apocalyptic number.

618639 is a deficient number, since it is larger than the sum of its proper divisors (337521).

618639 is a wasteful number, since it uses less digits than its factorization.

618639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430.

The product of its digits is 7776, while the sum is 33.

The square root of 618639 is about 786.5360767314. The cubic root of 618639 is about 85.2077501822.

The spelling of 618639 in words is "six hundred eighteen thousand, six hundred thirty-nine".