2222212221 has 6 divisors (see below), whose sum is σ = 3209862110. Its totient is φ = 1481474808.

The previous prime is 2222212211. The next prime is 2222212243. The reversal of 2222212221 is 1222122222.

2222212221 is a `hidden beast` number, since 222 + 221 + 2 + 221 = 666.

It can be written as a sum of positive squares in only one way, i.e., 2022300900 + 199911321 = 44970^2 + 14139^2 .

It is not a de Polignac number, because 2222212221 - 2⁵ = 2222212189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2222212194 and 2222212203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2222212211) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 123456226 + ... + 123456243.

Almost surely, 2^2222212221 is an apocalyptic number.

It is an amenable number.

2222212221 is a deficient number, since it is larger than the sum of its proper divisors (987649889).

2222212221 is a wasteful number, since it uses less digits than its factorization.

2222212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246912475 (or 246912472 counting only the distinct ones).

The product of its digits is 256, while the sum is 18.

The square root of 2222212221 is about 47140.3460000030. The cubic root of 2222212221 is about 1304.9539227136.

Adding to 2222212221 its reverse (1222122222), we get a palindrome (3444334443).

It can be divided in two parts, 22222 and 12221, that added together give a palindrome (34443).

The spelling of 2222212221 in words is "two billion, two hundred twenty-two million, two hundred twelve thousand, two hundred twenty-one".