1221100222012 has 36 divisors (see below), whose sum is σ = 2353881970440. Its totient is φ = 553856918560.

The previous prime is 1221100222007. The next prime is 1221100222021. The reversal of 1221100222012 is 2102220011221.

It is a happy number.

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 11 ways as a sum of consecutive naturals, for example, 2475187 + ... + 2927242.

It is an arithmetic number, because the mean of its divisors is an integer number (65385610290).

Almost surely, 2^{1221100222012} is an apocalyptic number.

It is an amenable number.

1221100222012 is a deficient number, since it is larger than the sum of its proper divisors (1132781748428).

1221100222012 is a wasteful number, since it uses less digits than its factorization.

1221100222012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5402922 (or 5402909 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1221100222012 its reverse (2102220011221), we get a palindrome (3323320233233).

The spelling of 1221100222012 in words is "one trillion, two hundred twenty-one billion, one hundred million, two hundred twenty-two thousand, twelve".