212021213221 has 4 divisors (see below), whose sum is σ = 216532302912. Its totient is φ = 207510123532.

The previous prime is 212021213189. The next prime is 212021213231. The reversal of 212021213221 is 122312120212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 212021213221 - 2⁵ = 212021213189 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 (212021213231) 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, 2255544775 + ... + 2255544868.

It is an arithmetic number, because the mean of its divisors is an integer number (54133075728).

Almost surely, 2^212021213221 is an apocalyptic number.

It is an amenable number.

212021213221 is a deficient number, since it is larger than the sum of its proper divisors (4511089691).

212021213221 is an equidigital number, since it uses as much as digits as its factorization.

212021213221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4511089690.

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

Adding to 212021213221 its reverse (122312120212), we get a palindrome (334333333433).

The spelling of 212021213221 in words is "two hundred twelve billion, twenty-one million, two hundred thirteen thousand, two hundred twenty-one".