655220 has 18 divisors (see below), whose sum is σ = 1383606. Its totient is φ = 260640.

The previous prime is 655219. The next prime is 655223. The reversal of 655220 is 22556.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 80656 + 574564 = 284^2 + 758^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 655192 and 655201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3530 + ... + 3710.

It is an arithmetic number, because the mean of its divisors is an integer number (76867).

2⁶⁵⁵²²⁰ is an apocalyptic number.

It is an amenable number.

655220 is an abundant number, since it is smaller than the sum of its proper divisors (728386).

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

655220 is a wasteful number, since it uses less digits than its factorization.

655220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 371 (or 188 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 655220 is about 809.4566078549. The cubic root of 655220 is about 86.8551780942.

Multiplying 655220 by its sum of digits (20), we get a square (13104400 = 3620²).

655220 divided by its sum of digits (20) gives a square (32761 = 181²).

Adding to 655220 its reverse (22556), we get a palindrome (677776).

The spelling of 655220 in words is "six hundred fifty-five thousand, two hundred twenty".