212221221021 has 8 divisors (see below), whose sum is σ = 314401808960. Its totient is φ = 141480813996.

The previous prime is 212221221013. The next prime is 212221221151. The reversal of 212221221021 is 120122122212.

It is a happy number.

212221221021 is a `hidden beast` number, since 212 + 221 + 2 + 210 + 21 = 666.

It is not a de Polignac number, because 212221221021 - 2³ = 212221221013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212221220985 and 212221221003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212221220021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3930022585 + ... + 3930022638.

It is an arithmetic number, because the mean of its divisors is an integer number (39300226120).

Almost surely, 2^212221221021 is an apocalyptic number.

It is an amenable number.

212221221021 is a deficient number, since it is larger than the sum of its proper divisors (102180587939).

212221221021 is an equidigital number, since it uses as much as digits as its factorization.

212221221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7860045232 (or 7860045226 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 212221221021 its reverse (120122122212), we get a palindrome (332343343233).

The spelling of 212221221021 in words is "two hundred twelve billion, two hundred twenty-one million, two hundred twenty-one thousand, twenty-one".