222120421 has 4 divisors (see below), whose sum is σ = 222374572. Its totient is φ = 221866272.

The previous prime is 222120401. The next prime is 222120473. The reversal of 222120421 is 124021222.

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 179935396 + 42185025 = 13414^2 + 6495^2 .

It is a cyclic number.

It is not a de Polignac number, because 222120421 - 2⁵ = 222120389 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 222120395 and 222120404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222120401) 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, 125760 + ... + 127513.

It is an arithmetic number, because the mean of its divisors is an integer number (55593643).

Almost surely, 2^222120421 is an apocalyptic number.

It is an amenable number.

222120421 is a deficient number, since it is larger than the sum of its proper divisors (254151).

222120421 is an equidigital number, since it uses as much as digits as its factorization.

222120421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254150.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 222120421 is about 14903.7049420605. The cubic root of 222120421 is about 605.6143576014.

Adding to 222120421 its reverse (124021222), we get a palindrome (346141643).

The spelling of 222120421 in words is "two hundred twenty-two million, one hundred twenty thousand, four hundred twenty-one".