212012021221 has 32 divisors (see below), whose sum is σ = 285587140608. Its totient is φ = 151999208640.

The previous prime is 212012021219. The next prime is 212012021231. The reversal of 212012021221 is 122120210212.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 212012021221 - 2¹ = 212012021219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 212012021195 and 212012021204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212012021231) 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, 37645 + ... + 652258.

It is an arithmetic number, because the mean of its divisors is an integer number (8924598144).

Almost surely, 2^212012021221 is an apocalyptic number.

It is an amenable number.

212012021221 is a deficient number, since it is larger than the sum of its proper divisors (73575119387).

212012021221 is a wasteful number, since it uses less digits than its factorization.

212012021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690241.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 212012021221 its reverse (122120210212), we get a palindrome (334132231433).

The spelling of 212012021221 in words is "two hundred twelve billion, twelve million, twenty-one thousand, two hundred twenty-one".