222222021 has 16 divisors (see below), whose sum is σ = 353347584. Its totient is φ = 121462704.

The previous prime is 222221971. The next prime is 222222029. The reversal of 222222021 is 120222222.

It is not a de Polignac number, because 222222021 - 2⁶ = 222221957 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222222029) 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 15 ways as a sum of consecutive naturals, for example, 229561 + ... + 230526.

It is an arithmetic number, because the mean of its divisors is an integer number (22084224).

Almost surely, 2^222222021 is an apocalyptic number.

222222021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

222222021 is a deficient number, since it is larger than the sum of its proper divisors (131125563).

222222021 is a wasteful number, since it uses less digits than its factorization.

222222021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 460120.

The product of its (nonzero) digits is 128, while the sum is 15.

The square root of 222222021 is about 14907.1131007986. The cubic root of 222222021 is about 605.7066814548.

Adding to 222222021 its reverse (120222222), we get a palindrome (342444243).

The spelling of 222222021 in words is "two hundred twenty-two million, two hundred twenty-two thousand, twenty-one".