1212030221 has 2 divisors, whose sum is σ = 1212030222. Its totient is φ = 1212030220.

The previous prime is 1212030217. The next prime is 1212030223. The reversal of 1212030221 is 1220302121.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1212014596 + 15625 = 34814^2 + 125^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212030221 - 2² = 1212030217 is a prime.

Together with 1212030223, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1212030196 and 1212030205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1212030223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606015110 + 606015111.

It is an arithmetic number, because the mean of its divisors is an integer number (606015111).

Almost surely, 2^1212030221 is an apocalyptic number.

It is an amenable number.

1212030221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212030221 is an equidigital number, since it uses as much as digits as its factorization.

1212030221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 1212030221 is about 34814.2244061246. The cubic root of 1212030221 is about 1066.1978839275.

Adding to 1212030221 its reverse (1220302121), we get a palindrome (2432332342).

The spelling of 1212030221 in words is "one billion, two hundred twelve million, thirty thousand, two hundred twenty-one".