21112210221212 has 24 divisors (see below), whose sum is σ = 40308967704432. Its totient is φ = 9595545120000.

The previous prime is 21112210221211. The next prime is 21112210221229. The reversal of 21112210221212 is 21212201221112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112210221211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22384493 + ... + 23308580.

It is an arithmetic number, because the mean of its divisors is an integer number (1679540321018).

Almost surely, 2^{21112210221212} is an apocalyptic number.

21112210221212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21112210221212 is a deficient number, since it is larger than the sum of its proper divisors (19196757483220).

21112210221212 is a wasteful number, since it uses less digits than its factorization.

21112210221212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45703589 (or 45703587 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 21112210221212 its reverse (21212201221112), we get a palindrome (42324411442324).

The spelling of 21112210221212 in words is "twenty-one trillion, one hundred twelve billion, two hundred ten million, two hundred twenty-one thousand, two hundred twelve".