212002001221 has 4 divisors (see below), whose sum is σ = 212002986700. Its totient is φ = 212001015744.

The previous prime is 212002001203. The next prime is 212002001243. The reversal of 212002001221 is 122100200212.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 146524356225 + 65477644996 = 382785^2 + 255886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212002001221 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 (212002001021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16836 + ... + 651373.

It is an arithmetic number, because the mean of its divisors is an integer number (53000746675).

Almost surely, 2^212002001221 is an apocalyptic number.

It is an amenable number.

212002001221 is a deficient number, since it is larger than the sum of its proper divisors (985479).

212002001221 is an equidigital number, since it uses as much as digits as its factorization.

212002001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 985478.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 212002001221 its reverse (122100200212), we get a palindrome (334102201433).

The spelling of 212002001221 in words is "two hundred twelve billion, two million, one thousand, two hundred twenty-one".