212120030221 has 6 divisors (see below), whose sum is σ = 233156727566. Its totient is φ = 192836391000.

The previous prime is 212120030179. The next prime is 212120030249. The reversal of 212120030221 is 122030021212.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 184891400100 + 27228630121 = 429990^2 + 165011^2 .

It is not a de Polignac number, because 212120030221 - 2¹³ = 212120022029 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212120030195 and 212120030204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212120030281) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 876528930 + ... + 876529171.

Almost surely, 2^212120030221 is an apocalyptic number.

It is an amenable number.

212120030221 is a deficient number, since it is larger than the sum of its proper divisors (21036697345).

212120030221 is a wasteful number, since it uses less digits than its factorization.

212120030221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1753058123 (or 1753058112 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 212120030221 its reverse (122030021212), we get a palindrome (334150051433).

Subtracting from 212120030221 its reverse (122030021212), we obtain a palindrome (90090009009).

The spelling of 212120030221 in words is "two hundred twelve billion, one hundred twenty million, thirty thousand, two hundred twenty-one".