222020021 has 4 divisors (see below), whose sum is σ = 226209132. Its totient is φ = 217830912.

The previous prime is 222020011. The next prime is 222020033. The reversal of 222020021 is 120020222.

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 90459121 + 131560900 = 9511^2 + 11470^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-222020021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 222019984 and 222020011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222020011) 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, 2094476 + ... + 2094581.

It is an arithmetic number, because the mean of its divisors is an integer number (56552283).

Almost surely, 2^222020021 is an apocalyptic number.

It is an amenable number.

222020021 is a deficient number, since it is larger than the sum of its proper divisors (4189111).

222020021 is an equidigital number, since it uses as much as digits as its factorization.

222020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4189110.

The product of its (nonzero) digits is 32, while the sum is 11.

The square root of 222020021 is about 14900.3362713732. The cubic root of 222020021 is about 605.5230965266.

Adding to 222020021 its reverse (120020222), we get a palindrome (342040243).

The spelling of 222020021 in words is "two hundred twenty-two million, twenty thousand, twenty-one".