1221211112201 has 2 divisors, whose sum is σ = 1221211112202. Its totient is φ = 1221211112200.

The previous prime is 1221211112123. The next prime is 1221211112249. The reversal of 1221211112201 is 1022111121221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 616144932601 + 605066179600 = 784949^2 + 777860^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221211112201 is a prime.

It is a super-2 number, since 2×1221211112201² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1221211112201.

It is not a weakly prime, because it can be changed into another prime (1221211112701) 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, 610605556100 + 610605556101.

It is an arithmetic number, because the mean of its divisors is an integer number (610605556101).

Almost surely, 2^{1221211112201} is an apocalyptic number.

It is an amenable number.

1221211112201 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221211112201 is an equidigital number, since it uses as much as digits as its factorization.

1221211112201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1221211112201 its reverse (1022111121221), we get a palindrome (2243322233422).

The spelling of 1221211112201 in words is "one trillion, two hundred twenty-one billion, two hundred eleven million, one hundred twelve thousand, two hundred one".