618655 has 4 divisors (see below), whose sum is σ = 742392. Its totient is φ = 494920.

The previous prime is 618643. The next prime is 618671. The reversal of 618655 is 556816.

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-618655 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61861 + ... + 61870.

It is an arithmetic number, because the mean of its divisors is an integer number (185598).

2⁶¹⁸⁶⁵⁵ is an apocalyptic number.

618655 is a deficient number, since it is larger than the sum of its proper divisors (123737).

618655 is a wasteful number, since it uses less digits than its factorization.

618655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123736.

The product of its digits is 7200, while the sum is 31.

The square root of 618655 is about 786.5462478456. The cubic root of 618655 is about 85.2084847582.

It can be divided in two parts, 6186 and 55, that added together give a square (6241 = 79²).

The spelling of 618655 in words is "six hundred eighteen thousand, six hundred fifty-five".