2221001856 has 160 divisors (see below), whose sum is σ = 6999024780. Its totient is φ = 696729600.

The previous prime is 2221001819. The next prime is 2221001869. The reversal of 2221001856 is 6581001222.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 2210504256 + 10497600 = 47016^2 + 3240^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 169956 + ... + 182556.

Almost surely, 2^2221001856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2221001856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3499512390).

2221001856 is an abundant number, since it is smaller than the sum of its proper divisors (4778022924).

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

2221001856 is a wasteful number, since it uses less digits than its factorization.

2221001856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12644 (or 12623 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 2221001856 is about 47127.5063630572. The cubic root of 2221001856 is about 1304.7169580367.

The spelling of 2221001856 in words is "two billion, two hundred twenty-one million, one thousand, eight hundred fifty-six".