2221001220 has 96 divisors (see below), whose sum is σ = 6401824128. Its totient is φ = 574912512.

The previous prime is 2221001207. The next prime is 2221001243. The reversal of 2221001220 is 221001222.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 2221001196 and 2221001205.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1248972 + ... + 1250748.

It is an arithmetic number, because the mean of its divisors is an integer number (66685668).

Almost surely, 2^2221001220 is an apocalyptic number.

2221001220 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 2221001220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3200912064).

2221001220 is an abundant number, since it is smaller than the sum of its proper divisors (4180822908).

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

2221001220 is a wasteful number, since it uses less digits than its factorization.

2221001220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2389 (or 2387 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 2221001220 is about 47127.4996154050. The cubic root of 2221001220 is about 1304.7168334983.

Adding to 2221001220 its reverse (221001222), we get a palindrome (2442002442).

The spelling of 2221001220 in words is "two billion, two hundred twenty-one million, one thousand, two hundred twenty".