212106022021 has 4 divisors (see below), whose sum is σ = 212347876972. Its totient is φ = 211864167072.

The previous prime is 212106022013. The next prime is 212106022027. The reversal of 212106022021 is 120220601212.

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 176681512225 + 35424509796 = 420335^2 + 188214^2 .

It is a cyclic number.

It is not a de Polignac number, because 212106022021 - 2³ = 212106022013 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 212106022021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212106022027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120926160 + ... + 120927913.

It is an arithmetic number, because the mean of its divisors is an integer number (53086969243).

Almost surely, 2^212106022021 is an apocalyptic number.

It is an amenable number.

212106022021 is a deficient number, since it is larger than the sum of its proper divisors (241854951).

212106022021 is an equidigital number, since it uses as much as digits as its factorization.

212106022021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241854950.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 212106022021 its reverse (120220601212), we get a palindrome (332326623233).

The spelling of 212106022021 in words is "two hundred twelve billion, one hundred six million, twenty-two thousand, twenty-one".