225656640 has 336 divisors, whose sum is σ = 898672320. Its totient is φ = 51363840.

The previous prime is 225656633. The next prime is 225656653. The reversal of 225656640 is 46656522.

225656640 is a `hidden beast` number, since 2 + 2 + 5 + 6 + 5 + 6 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 225656595 and 225656604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 538351 + ... + 538769.

It is an arithmetic number, because the mean of its divisors is an integer number (2674620).

Almost surely, 2^225656640 is an apocalyptic number.

225656640 is a gapful number since it is divisible by the number (20) 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 225656640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (449336160).

225656640 is an abundant number, since it is smaller than the sum of its proper divisors (673015680).

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

225656640 is a wasteful number, since it uses less digits than its factorization.

225656640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 470 (or 457 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 225656640 is about 15021.8720537755. The cubic root of 225656640 is about 608.8113015159.

The spelling of 225656640 in words is "two hundred twenty-five million, six hundred fifty-six thousand, six hundred forty".