1221221222 has 8 divisors (see below), whose sum is σ = 1972742016. Its totient is φ = 563640552.

The previous prime is 1221221207. The next prime is 1221221249. The reversal of 1221221222 is 2221221221.

It is a happy number.

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 self number, because there is not a number n which added to its sum of digits gives 1221221222.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23484998 + ... + 23485049.

It is an arithmetic number, because the mean of its divisors is an integer number (246592752).

Almost surely, 2^1221221222 is an apocalyptic number.

1221221222 is a deficient number, since it is larger than the sum of its proper divisors (751520794).

1221221222 is a wasteful number, since it uses less digits than its factorization.

1221221222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46970062.

The product of its digits is 128, while the sum is 17.

The square root of 1221221222 is about 34945.9757625968. The cubic root of 1221221222 is about 1068.8861445887.

Adding to 1221221222 its reverse (2221221221), we get a palindrome (3442442443).

Subtracting 1221221222 from its reverse (2221221221), we obtain a palindrome (999999999).

The spelling of 1221221222 in words is "one billion, two hundred twenty-one million, two hundred twenty-one thousand, two hundred twenty-two".