21212123100212 has 24 divisors (see below), whose sum is σ = 40496785110432. Its totient is φ = 9641656580000.

The previous prime is 21212123100209. The next prime is 21212123100239. The reversal of 21212123100212 is 21200132121212.

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 7 ways as a sum of consecutive naturals, for example, 3458618 + ... + 7374705.

It is an arithmetic number, because the mean of its divisors is an integer number (1687366046268).

Almost surely, 2^{21212123100212} is an apocalyptic number.

21212123100212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21212123100212 is a deficient number, since it is larger than the sum of its proper divisors (19284662010220).

21212123100212 is a wasteful number, since it uses less digits than its factorization.

21212123100212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10877839 (or 10877837 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21212123100212 its reverse (21200132121212), we get a palindrome (42412255221424).

The spelling of 21212123100212 in words is "twenty-one trillion, two hundred twelve billion, one hundred twenty-three million, one hundred thousand, two hundred twelve".