1220288256 has 216 divisors, whose sum is σ = 3888546480. Its totient is φ = 364953600.

The previous prime is 1220288249. The next prime is 1220288257. The reversal of 1220288256 is 6528820221.

1220288256 is a `hidden beast` number, since 122 + 0 + 288 + 256 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 1220288256.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220288257) 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, 2255346 + ... + 2255886.

It is an arithmetic number, because the mean of its divisors is an integer number (18002530).

Almost surely, 2^1220288256 is an apocalyptic number.

1220288256 is a gapful number since it is divisible by the number (16) 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 1220288256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1944273240).

1220288256 is an abundant number, since it is smaller than the sum of its proper divisors (2668258224).

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

1220288256 is a wasteful number, since it uses less digits than its factorization.

1220288256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 663 (or 646 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 1220288256 is about 34932.6245220711. The cubic root of 1220288256 is about 1068.6138792884.

The spelling of 1220288256 in words is "one billion, two hundred twenty million, two hundred eighty-eight thousand, two hundred fifty-six".