1212112100221 has 16 divisors (see below), whose sum is σ = 1329166080000. Its totient is φ = 1096203596400.

The previous prime is 1212112100189. The next prime is 1212112100239. The reversal of 1212112100221 is 1220012112121.

It is not a de Polignac number, because 1212112100221 - 2⁵ = 1212112100189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1212112100195 and 1212112100204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212112100291) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 14403256 + ... + 14487166.

It is an arithmetic number, because the mean of its divisors is an integer number (83072880000).

Almost surely, 2^{1212112100221} is an apocalyptic number.

1212112100221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1212112100221 is a deficient number, since it is larger than the sum of its proper divisors (117053979779).

1212112100221 is a wasteful number, since it uses less digits than its factorization.

1212112100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90720.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1212112100221 its reverse (1220012112121), we get a palindrome (2432124212342).

The spelling of 1212112100221 in words is "one trillion, two hundred twelve billion, one hundred twelve million, one hundred thousand, two hundred twenty-one".