21111221100212 has 12 divisors (see below), whose sum is σ = 36945722780736. Its totient is φ = 10555300305720.

The previous prime is 21111221100169. The next prime is 21111221100239. The reversal of 21111221100212 is 21200112211112.

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, 77407958 + ... + 77680205.

It is an arithmetic number, because the mean of its divisors is an integer number (3078810231728).

Almost surely, 2^{21111221100212} is an apocalyptic number.

It is an amenable number.

21111221100212 is a deficient number, since it is larger than the sum of its proper divisors (15834501680524).

21111221100212 is a wasteful number, since it uses less digits than its factorization.

21111221100212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155122198 (or 155122196 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21111221100212 its reverse (21200112211112), we get a palindrome (42311333311324).

The spelling of 21111221100212 in words is "twenty-one trillion, one hundred eleven billion, two hundred twenty-one million, one hundred thousand, two hundred twelve".