655620 has 72 divisors (see below), whose sum is σ = 2145024. Its totient is φ = 149184.

The previous prime is 655601. The next prime is 655637. The reversal of 655620 is 26556.

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

655620 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2829 + ... + 3051.

It is an arithmetic number, because the mean of its divisors is an integer number (29792).

2⁶⁵⁵⁶²⁰ is an apocalyptic number.

655620 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 655620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1072512).

655620 is an abundant number, since it is smaller than the sum of its proper divisors (1489404).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

655620 is a wasteful number, since it uses less digits than its factorization.

655620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 655620 is about 809.7036494916. The cubic root of 655620 is about 86.8728490056.

It can be divided in two parts, 655 and 620, that added together give a triangular number (1275 = T₅₀).

The spelling of 655620 in words is "six hundred fifty-five thousand, six hundred twenty".