2221223221 has 4 divisors (see below), whose sum is σ = 2538540832. Its totient is φ = 1903905612.

The previous prime is 2221223203. The next prime is 2221223233. The reversal of 2221223221 is 1223221222.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1223221222 = 2 ⋅611610611.

It is not a de Polignac number, because 2221223221 - 2¹⁷ = 2221092149 is a prime.

It is a super-2 number, since 2×2221223221² = 9867665195019229682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2221223261) 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, 158658795 + ... + 158658808.

It is an arithmetic number, because the mean of its divisors is an integer number (634635208).

Almost surely, 2^2221223221 is an apocalyptic number.

It is an amenable number.

2221223221 is a deficient number, since it is larger than the sum of its proper divisors (317317611).

2221223221 is an equidigital number, since it uses as much as digits as its factorization.

2221223221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317317610.

The product of its digits is 384, while the sum is 19.

The square root of 2221223221 is about 47129.8548798954. The cubic root of 2221223221 is about 1304.7603032015.

Adding to 2221223221 its reverse (1223221222), we get a palindrome (3444444443).

The spelling of 2221223221 in words is "two billion, two hundred twenty-one million, two hundred twenty-three thousand, two hundred twenty-one".