655145220 has 72 divisors (see below), whose sum is σ = 1874646144. Its totient is φ = 170953664.

The previous prime is 655145159. The next prime is 655145221. The reversal of 655145220 is 22541556.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (655145221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 130069 + ... + 135011.

It is an arithmetic number, because the mean of its divisors is an integer number (26036752).

Almost surely, 2^655145220 is an apocalyptic number.

655145220 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 655145220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (937323072).

655145220 is an abundant number, since it is smaller than the sum of its proper divisors (1219500924).

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

655145220 is a wasteful number, since it uses less digits than its factorization.

655145220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5049 (or 5000 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

The square root of 655145220 is about 25595.8047343700. The cubic root of 655145220 is about 868.5187371938.

Adding to 655145220 its reverse (22541556), we get a palindrome (677686776).

The spelling of 655145220 in words is "six hundred fifty-five million, one hundred forty-five thousand, two hundred twenty".