1221011232211 has 2 divisors, whose sum is σ = 1221011232212. Its totient is φ = 1221011232210.

The previous prime is 1221011232209. The next prime is 1221011232223. The reversal of 1221011232211 is 1122321101221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221011232211 - 2¹ = 1221011232209 is a prime.

Together with 1221011232209, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1221011232241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610505616105 + 610505616106.

It is an arithmetic number, because the mean of its divisors is an integer number (610505616106).

Almost surely, 2^{1221011232211} is an apocalyptic number.

1221011232211 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221011232211 is an equidigital number, since it uses as much as digits as its factorization.

1221011232211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 1221011232211 its reverse (1122321101221), we get a palindrome (2343332333432).

The spelling of 1221011232211 in words is "one trillion, two hundred twenty-one billion, eleven million, two hundred thirty-two thousand, two hundred eleven".