1222221100221 has 24 divisors (see below), whose sum is σ = 1926888878304. Its totient is φ = 740369014560.

The previous prime is 1222221100211. The next prime is 1222221100273. The reversal of 1222221100221 is 1220011222221.

It is a happy number.

1222221100221 is a `hidden beast` number, since 1 + 222 + 221 + 1 + 0 + 0 + 221 = 666.

It is not a de Polignac number, because 1222221100221 - 2⁵ = 1222221100189 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1222221100194 and 1222221100203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1222221100211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2893351 + ... + 3288756.

It is an arithmetic number, because the mean of its divisors is an integer number (80287036596).

Almost surely, 2^{1222221100221} is an apocalyptic number.

1222221100221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1222221100221 is a deficient number, since it is larger than the sum of its proper divisors (704667778083).

1222221100221 is a wasteful number, since it uses less digits than its factorization.

1222221100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6184121 (or 6184118 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 1222221100221 its reverse (1220011222221), we get a palindrome (2442232322442).

The spelling of 1222221100221 in words is "one trillion, two hundred twenty-two billion, two hundred twenty-one million, one hundred thousand, two hundred twenty-one".