212123133320221 has 4 divisors (see below), whose sum is σ = 212138223547932. Its totient is φ = 212108043092512.

The previous prime is 212123133320213. The next prime is 212123133320323. The reversal of 212123133320221 is 122023331321212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 48170345916196 + 163952787404025 = 6940486^2 + 12804405^2 .

It is a cyclic number.

It is not a de Polignac number, because 212123133320221 - 2³ = 212123133320213 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 212123133320221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212123133320621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7545092770 + ... + 7545120883.

It is an arithmetic number, because the mean of its divisors is an integer number (53034555886983).

Almost surely, 2^{212123133320221} is an apocalyptic number.

It is an amenable number.

212123133320221 is a deficient number, since it is larger than the sum of its proper divisors (15090227711).

212123133320221 is a wasteful number, since it uses less digits than its factorization.

212123133320221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15090227710.

The product of its (nonzero) digits is 5184, while the sum is 28.

Adding to 212123133320221 its reverse (122023331321212), we get a palindrome (334146464641433).

The spelling of 212123133320221 in words is "two hundred twelve trillion, one hundred twenty-three billion, one hundred thirty-three million, three hundred twenty thousand, two hundred twenty-one".