656220 has 24 divisors (see below), whose sum is σ = 1837584. Its totient is φ = 174976.

The previous prime is 656171. The next prime is 656221. The reversal of 656220 is 22656.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 656220.

It is not an unprimeable number, because it can be changed into a prime (656221) by changing a digit.

656220 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 7 ways as a sum of consecutive naturals, for example, 5409 + ... + 5528.

It is an arithmetic number, because the mean of its divisors is an integer number (76566).

2⁶⁵⁶²²⁰ is an apocalyptic number.

656220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

656220 is an abundant number, since it is smaller than the sum of its proper divisors (1181364).

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

656220 is a wasteful number, since it uses less digits than its factorization.

656220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10949 (or 10947 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 656220 is about 810.0740706874. The cubic root of 656220 is about 86.8993419014.

Adding to 656220 its reverse (22656), we get a palindrome (678876).

The spelling of 656220 in words is "six hundred fifty-six thousand, two hundred twenty".