1221021201011 has 4 divisors (see below), whose sum is σ = 1221029871072. Its totient is φ = 1221012530952.

The previous prime is 1221021200911. The next prime is 1221021201031. The reversal of 1221021201011 is 1101021201221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221021201011 - 2¹⁰ = 1221021199987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221021201031) 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 in 3 ways as a sum of consecutive naturals, for example, 4120235 + ... + 4406628.

It is an arithmetic number, because the mean of its divisors is an integer number (305257467768).

Almost surely, 2^{1221021201011} is an apocalyptic number.

1221021201011 is a deficient number, since it is larger than the sum of its proper divisors (8670061).

1221021201011 is an equidigital number, since it uses as much as digits as its factorization.

1221021201011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8670060.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1221021201011 its reverse (1101021201221), we get a palindrome (2322042402232).

The spelling of 1221021201011 in words is "one trillion, two hundred twenty-one billion, twenty-one million, two hundred one thousand, eleven".