222121002220021 has 4 divisors (see below), whose sum is σ = 222121062463500. Its totient is φ = 222120941976544.

The previous prime is 222121002220001. The next prime is 222121002220043. The reversal of 222121002220021 is 120022200121222.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 179661586364100 + 42459415855921 = 13403790^2 + 6516089^2 .

It is a cyclic number.

It is not a de Polignac number, because 222121002220021 - 2³⁵ = 222086642481653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222121002220001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24203566 + ... + 32094463.

It is an arithmetic number, because the mean of its divisors is an integer number (55530265615875).

Almost surely, 2^{222121002220021} is an apocalyptic number.

It is an amenable number.

222121002220021 is a deficient number, since it is larger than the sum of its proper divisors (60243479).

222121002220021 is an equidigital number, since it uses as much as digits as its factorization.

222121002220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60243478.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 222121002220021 its reverse (120022200121222), we get a palindrome (342143202341243).

The spelling of 222121002220021 in words is "two hundred twenty-two trillion, one hundred twenty-one billion, two million, two hundred twenty thousand, twenty-one".