1221002210209 has 2 divisors, whose sum is σ = 1221002210210. Its totient is φ = 1221002210208.

The previous prime is 1221002210189. The next prime is 1221002210213. The reversal of 1221002210209 is 9020122001221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1154217179025 + 66785031184 = 1074345^2 + 258428^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221002210209 - 2⁷ = 1221002210081 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1221002210209.

It is not a weakly prime, because it can be changed into another prime (1221002210509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610501105104 + 610501105105.

It is an arithmetic number, because the mean of its divisors is an integer number (610501105105).

Almost surely, 2^{1221002210209} is an apocalyptic number.

It is an amenable number.

1221002210209 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221002210209 is an equidigital number, since it uses as much as digits as its factorization.

1221002210209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 22.

The spelling of 1221002210209 in words is "one trillion, two hundred twenty-one billion, two million, two hundred ten thousand, two hundred nine".