1221300321091 has 2 divisors, whose sum is σ = 1221300321092. Its totient is φ = 1221300321090.

The previous prime is 1221300321089. The next prime is 1221300321127. The reversal of 1221300321091 is 1901230031221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221300321091 - 2¹ = 1221300321089 is a prime.

Together with 1221300321089, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1221300322091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610650160545 + 610650160546.

It is an arithmetic number, because the mean of its divisors is an integer number (610650160546).

Almost surely, 2^{1221300321091} is an apocalyptic number.

1221300321091 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221300321091 is an equidigital number, since it uses as much as digits as its factorization.

1221300321091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 25.

The spelling of 1221300321091 in words is "one trillion, two hundred twenty-one billion, three hundred million, three hundred twenty-one thousand, ninety-one".