2221121021 has 16 divisors (see below), whose sum is σ = 2584483200. Its totient is φ = 1869350208.

The previous prime is 2221120999. The next prime is 2221121051. The reversal of 2221121021 is 1201211222.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2221121021 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2221120987 and 2221121005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2221121051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 415715 + ... + 421023.

It is an arithmetic number, because the mean of its divisors is an integer number (161530200).

Almost surely, 2^2221121021 is an apocalyptic number.

It is an amenable number.

2221121021 is a deficient number, since it is larger than the sum of its proper divisors (363362179).

2221121021 is a wasteful number, since it uses less digits than its factorization.

2221121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6388.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 2221121021 is about 47128.7706289905. The cubic root of 2221121021 is about 1304.7402919232.

Adding to 2221121021 its reverse (1201211222), we get a palindrome (3422332243).

The spelling of 2221121021 in words is "two billion, two hundred twenty-one million, one hundred twenty-one thousand, twenty-one".