222424021 has 4 divisors (see below), whose sum is σ = 224047692. Its totient is φ = 220800352.

The previous prime is 222424019. The next prime is 222424031. The reversal of 222424021 is 120424222.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120424222 = 2 ⋅60212111.

It can be written as a sum of positive squares in 2 ways, for example, as 98903025 + 123520996 = 9945^2 + 11114^2 .

It is a cyclic number.

It is not a de Polignac number, because 222424021 - 2¹ = 222424019 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 222424021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222424031) 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, 811630 + ... + 811903.

It is an arithmetic number, because the mean of its divisors is an integer number (56011923).

Almost surely, 2^222424021 is an apocalyptic number.

It is an amenable number.

222424021 is a deficient number, since it is larger than the sum of its proper divisors (1623671).

222424021 is a wasteful number, since it uses less digits than its factorization.

222424021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1623670.

The product of its (nonzero) digits is 512, while the sum is 19.

The square root of 222424021 is about 14913.8868508515. The cubic root of 222424021 is about 605.8901551641.

Adding to 222424021 its reverse (120424222), we get a palindrome (342848243).

The spelling of 222424021 in words is "two hundred twenty-two million, four hundred twenty-four thousand, twenty-one".