1221021100012 has 24 divisors (see below), whose sum is σ = 2442111472640. Its totient is φ = 523279913040.

The previous prime is 1221021100009. The next prime is 1221021100043. The reversal of 1221021100012 is 2100011201221.

It is a junction number, because it is equal to n+sod(n) for n = 1221021099965 and 1221021100001.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 416587 + ... + 1617277.

Almost surely, 2^{1221021100012} is an apocalyptic number.

It is an amenable number.

1221021100012 is an abundant number, since it is smaller than the sum of its proper divisors (1221090372628).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221021100012 is a wasteful number, since it uses less digits than its factorization.

1221021100012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1237021 (or 1237019 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 1221021100012 its reverse (2100011201221), we get a palindrome (3321032301233).

The spelling of 1221021100012 in words is "one trillion, two hundred twenty-one billion, twenty-one million, one hundred thousand, twelve".