1221102011221 has 4 divisors (see below), whose sum is σ = 1221294529312. Its totient is φ = 1220909493132.

The previous prime is 1221102011209. The next prime is 1221102011237.

1221102011221 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1221102011221 - 2³⁷ = 1083663057749 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221102011195 and 1221102011204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221102017221) 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, 96249531 + ... + 96262216.

It is an arithmetic number, because the mean of its divisors is an integer number (305323632328).

Almost surely, 2^{1221102011221} is an apocalyptic number.

It is an amenable number.

1221102011221 is a deficient number, since it is larger than the sum of its proper divisors (192518091).

1221102011221 is an equidigital number, since it uses as much as digits as its factorization.

1221102011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192518090.

The product of its (nonzero) digits is 32, while the sum is 16.

The spelling of 1221102011221 in words is "one trillion, two hundred twenty-one billion, one hundred two million, eleven thousand, two hundred twenty-one".