21101112212212 has 18 divisors (see below), whose sum is σ = 39226894590422. Its totient is φ = 9929935158144.

The previous prime is 21101112212113. The next prime is 21101112212233. The reversal of 21101112212212 is 21221221110112.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 10934159075856 + 10166953136356 = 3306684^2 + 3188566^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21101112212212.

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 5 ways as a sum of consecutive naturals, for example, 9126777483 + ... + 9126779794.

Almost surely, 2^{21101112212212} is an apocalyptic number.

It is an amenable number.

21101112212212 is a deficient number, since it is larger than the sum of its proper divisors (18125782378210).

21101112212212 is a wasteful number, since it uses less digits than its factorization.

21101112212212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18253557315 (or 18253557296 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21101112212212 its reverse (21221221110112), we get a palindrome (42322333322324).

The spelling of 21101112212212 in words is "twenty-one trillion, one hundred one billion, one hundred twelve million, two hundred twelve thousand, two hundred twelve".