1222221001221 has 48 divisors (see below), whose sum is σ = 2094327638208. Its totient is φ = 678324672000.

The previous prime is 1222221001219. The next prime is 1222221001273. The reversal of 1222221001221 is 1221001222221.

It is a happy number.

1222221001221 is a `hidden beast` number, since 1 + 222 + 221 + 0 + 0 + 1 + 221 = 666.

It is not a de Polignac number, because 1222221001221 - 2¹ = 1222221001219 is a prime.

It is a super-3 number, since 3×1222221001221³ (a number of 37 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1222221001194 and 1222221001203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1222221001291) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9751455 + ... + 9875996.

It is an arithmetic number, because the mean of its divisors is an integer number (43631825796).

Almost surely, 2^{1222221001221} is an apocalyptic number.

1222221001221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1222221001221 is a deficient number, since it is larger than the sum of its proper divisors (872106636987).

1222221001221 is a wasteful number, since it uses less digits than its factorization.

1222221001221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19627522 (or 19627519 counting only the distinct ones).

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

Adding to 1222221001221 its reverse (1221001222221), we get a palindrome (2443222223442).

The spelling of 1222221001221 in words is "one trillion, two hundred twenty-two billion, two hundred twenty-one million, one thousand, two hundred twenty-one".