1221012021211 has 2 divisors, whose sum is σ = 1221012021212. Its totient is φ = 1221012021210.

The previous prime is 1221012021167. The next prime is 1221012021247. The reversal of 1221012021211 is 1121202101221.

It is a strong prime.

It is an emirp because it is prime and its reverse (1121202101221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221012021211 - 2¹⁷ = 1221011890139 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221012021611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610506010605 + 610506010606.

It is an arithmetic number, because the mean of its divisors is an integer number (610506010606).

Almost surely, 2^{1221012021211} is an apocalyptic number.

1221012021211 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221012021211 is an equidigital number, since it uses as much as digits as its factorization.

1221012021211 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1221012021211 its reverse (1121202101221), we get a palindrome (2342214122432).

The spelling of 1221012021211 in words is "one trillion, two hundred twenty-one billion, twelve million, twenty-one thousand, two hundred eleven".