1221212011100 has 36 divisors (see below), whose sum is σ = 2650748836008. Its totient is φ = 488352312000.

The previous prime is 1221212011057. The next prime is 1221212011111. The reversal of 1221212011100 is 11102121221.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1285211 + ... + 2023410.

Almost surely, 2^{1221212011100} is an apocalyptic number.

1221212011100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221212011100 is an abundant number, since it is smaller than the sum of its proper divisors (1429536824908).

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

1221212011100 is a wasteful number, since it uses less digits than its factorization.

1221212011100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3312326 (or 3312319 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1221212011100 its reverse (11102121221), we get a palindrome (1232314132321).

The spelling of 1221212011100 in words is "one trillion, two hundred twenty-one billion, two hundred twelve million, eleven thousand, one hundred".