2221220021100 has 144 divisors (see below), whose sum is σ = 6777355804800. Its totient is φ = 560123665920.

The previous prime is 2221220021089. The next prime is 2221220021129. The reversal of 2221220021100 is 11200221222.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 2221220021100.

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, 2761696 + ... + 3474104.

Almost surely, 2^{2221220021100} is an apocalyptic number.

2221220021100 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 2221220021100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3388677902400).

2221220021100 is an abundant number, since it is smaller than the sum of its proper divisors (4556135783700).

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

2221220021100 is a wasteful number, since it uses less digits than its factorization.

2221220021100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712992 (or 712985 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 2221220021100 its reverse (11200221222), we get a palindrome (2232420242322).

The spelling of 2221220021100 in words is "two trillion, two hundred twenty-one billion, two hundred twenty million, twenty-one thousand, one hundred".