212111201022121 has 4 divisors (see below), whose sum is σ = 212267050546644. Its totient is φ = 211955351497600.

The previous prime is 212111201022067. The next prime is 212111201022137. The reversal of 212111201022121 is 121220102111212.

It is a happy number.

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 51191320445721 + 160919880576400 = 7154811^2 + 12685420^2 .

It is a cyclic number.

It is not a de Polignac number, because 212111201022121 - 2¹⁷ = 212111200891049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (212111201022421) 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, 77924760220 + ... + 77924762941.

It is an arithmetic number, because the mean of its divisors is an integer number (53066762636661).

Almost surely, 2^{212111201022121} is an apocalyptic number.

It is an amenable number.

212111201022121 is a deficient number, since it is larger than the sum of its proper divisors (155849524523).

212111201022121 is a wasteful number, since it uses less digits than its factorization.

212111201022121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155849524522.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 212111201022121 its reverse (121220102111212), we get a palindrome (333331303133333).

The spelling of 212111201022121 in words is "two hundred twelve trillion, one hundred eleven billion, two hundred one million, twenty-two thousand, one hundred twenty-one".