222021021 has 4 divisors (see below), whose sum is σ = 296028032. Its totient is φ = 148014012.

The previous prime is 222021017. The next prime is 222021067. The reversal of 222021021 is 120120222.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 222021021 - 2² = 222021017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 222020988 and 222021006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222021011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37003501 + ... + 37003506.

It is an arithmetic number, because the mean of its divisors is an integer number (74007008).

Almost surely, 2^222021021 is an apocalyptic number.

It is an amenable number.

222021021 is a deficient number, since it is larger than the sum of its proper divisors (74007011).

222021021 is an equidigital number, since it uses as much as digits as its factorization.

222021021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74007010.

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 222021021 is about 14900.3698276251. The cubic root of 222021021 is about 605.5240056371.

Adding to 222021021 its reverse (120120222), we get a palindrome (342141243).

The spelling of 222021021 in words is "two hundred twenty-two million, twenty-one thousand, twenty-one".