212221211021 has 32 divisors (see below), whose sum is σ = 220586446080. Its totient is φ = 204087527424.

The previous prime is 212221210973. The next prime is 212221211023. The reversal of 212221211021 is 120112122212.

It is a cyclic number.

It is not a de Polignac number, because 212221211021 - 2¹⁰ = 212221209997 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 (212221211023) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 205441121 + ... + 205442153.

It is an arithmetic number, because the mean of its divisors is an integer number (6893326440).

Almost surely, 2^212221211021 is an apocalyptic number.

It is an amenable number.

212221211021 is a deficient number, since it is larger than the sum of its proper divisors (8365235059).

212221211021 is a wasteful number, since it uses less digits than its factorization.

212221211021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1605.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 212221211021 its reverse (120112122212), we get a palindrome (332333333233).

The spelling of 212221211021 in words is "two hundred twelve billion, two hundred twenty-one million, two hundred eleven thousand, twenty-one".