1212012021221 has 2 divisors, whose sum is σ = 1212012021222. Its totient is φ = 1212012021220.

The previous prime is 1212012021149. The next prime is 1212012021257. The reversal of 1212012021221 is 1221202102121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 686221708225 + 525790312996 = 828385^2 + 725114^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1212012021221 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1212012021221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1212012021271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606006010610 + 606006010611.

It is an arithmetic number, because the mean of its divisors is an integer number (606006010611).

Almost surely, 2^{1212012021221} is an apocalyptic number.

It is an amenable number.

1212012021221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212012021221 is an equidigital number, since it uses as much as digits as its factorization.

1212012021221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 1212012021221 its reverse (1221202102121), we get a palindrome (2433214123342).

The spelling of 1212012021221 in words is "one trillion, two hundred twelve billion, twelve million, twenty-one thousand, two hundred twenty-one".