1221012321211 has 8 divisors (see below), whose sum is σ = 1249658408240. Its totient is φ = 1192377618432.

The previous prime is 1221012321167. The next prime is 1221012321229. The reversal of 1221012321211 is 1121232101221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221012321211 - 2³⁹ = 671256507323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221012351211) 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 7 ways as a sum of consecutive naturals, for example, 2628846 + ... + 3058243.

It is an arithmetic number, because the mean of its divisors is an integer number (156207301030).

Almost surely, 2^{1221012321211} is an apocalyptic number.

1221012321211 is a deficient number, since it is larger than the sum of its proper divisors (28646087029).

1221012321211 is an equidigital number, since it uses as much as digits as its factorization.

1221012321211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5692125.

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

Adding to 1221012321211 its reverse (1121232101221), we get a palindrome (2342244422432).

The spelling of 1221012321211 in words is "one trillion, two hundred twenty-one billion, twelve million, three hundred twenty-one thousand, two hundred eleven".