222021 has 10 divisors (see below), whose sum is σ = 331782. Its totient is φ = 147960.

The previous prime is 222011. The next prime is 222023. The reversal of 222021 is 120222.

222021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 171396 + 50625 = 414^2 + 225^2 .

It is not a de Polignac number, because 222021 - 2⁵ = 221989 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

222021 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 221994 and 222012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222023) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1290 + ... + 1451.

2²²²⁰²¹ is an apocalyptic number.

It is an amenable number.

222021 is a deficient number, since it is larger than the sum of its proper divisors (109761).

222021 is an equidigital number, since it uses as much as digits as its factorization.

222021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2753 (or 2744 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 222021 is about 471.1910440575. The cubic root of 222021 is about 60.5523986546.

Adding to 222021 its reverse (120222), we get a palindrome (342243).

The spelling of 222021 in words is "two hundred twenty-two thousand, twenty-one", and thus it is an iban number.