221221022212 has 6 divisors (see below), whose sum is σ = 387136788878. Its totient is φ = 110610511104.

The previous prime is 221221022201. The next prime is 221221022221. The reversal of 221221022212 is 212220122122.

It can be written as a sum of positive squares in only one way, i.e., 202037664196 + 19183358016 = 449486^2 + 138504^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 221221022212.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27652627773 + ... + 27652627780.

Almost surely, 2^221221022212 is an apocalyptic number.

It is an amenable number.

221221022212 is a deficient number, since it is larger than the sum of its proper divisors (165915766666).

221221022212 is a wasteful number, since it uses less digits than its factorization.

221221022212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55305255557 (or 55305255555 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 221221022212 its reverse (212220122122), we get a palindrome (433441144334).

The spelling of 221221022212 in words is "two hundred twenty-one billion, two hundred twenty-one million, twenty-two thousand, two hundred twelve".