1221101100212 has 24 divisors (see below), whose sum is σ = 2456826175104. Its totient is φ = 520195334112.

The previous prime is 1221101100157. The next prime is 1221101100283. The reversal of 1221101100212 is 2120011011221.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 130566443 + ... + 130575794.

It is an arithmetic number, because the mean of its divisors is an integer number (102367757296).

Almost surely, 2^{1221101100212} is an apocalyptic number.

It is an amenable number.

1221101100212 is an abundant number, since it is smaller than the sum of its proper divisors (1235725074892).

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

1221101100212 is a wasteful number, since it uses less digits than its factorization.

1221101100212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261142415 (or 261142413 counting only the distinct ones).

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

Adding to 1221101100212 its reverse (2120011011221), we get a palindrome (3341112111433).

The spelling of 1221101100212 in words is "one trillion, two hundred twenty-one billion, one hundred one million, one hundred thousand, two hundred twelve".