1221212221222 has 8 divisors (see below), whose sum is σ = 2093506664976. Its totient is φ = 523376666232.

The previous prime is 1221212221217. The next prime is 1221212221241. The reversal of 1221212221222 is 2221222121221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 1221212221193 and 1221212221202.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43614722173 + ... + 43614722200.

It is an arithmetic number, because the mean of its divisors is an integer number (261688333122).

Almost surely, 2^{1221212221222} is an apocalyptic number.

1221212221222 is a deficient number, since it is larger than the sum of its proper divisors (872294443754).

1221212221222 is an equidigital number, since it uses as much as digits as its factorization.

1221212221222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87229444382.

The product of its digits is 512, while the sum is 22.

Adding to 1221212221222 its reverse (2221222121221), we get a palindrome (3442434342443).

The spelling of 1221212221222 in words is "one trillion, two hundred twenty-one billion, two hundred twelve million, two hundred twenty-one thousand, two hundred twenty-two".