212120212100221 has 4 divisors (see below), whose sum is σ = 212405703638112. Its totient is φ = 211834720562332.

The previous prime is 212120212100141. The next prime is 212120212100233. The reversal of 212120212100221 is 122001212021212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 212120212100221 - 2¹³ = 212120212092029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212120212100021) 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 3 ways as a sum of consecutive naturals, for example, 142745767831 + ... + 142745769316.

It is an arithmetic number, because the mean of its divisors is an integer number (53101425909528).

Almost surely, 2^{212120212100221} is an apocalyptic number.

It is an amenable number.

212120212100221 is a deficient number, since it is larger than the sum of its proper divisors (285491537891).

212120212100221 is an equidigital number, since it uses as much as digits as its factorization.

212120212100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285491537890.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 212120212100221 its reverse (122001212021212), we get a palindrome (334121424121433).

The spelling of 212120212100221 in words is "two hundred twelve trillion, one hundred twenty billion, two hundred twelve million, one hundred thousand, two hundred twenty-one".