1221112002221 has 16 divisors (see below), whose sum is σ = 1238273498880. Its totient is φ = 1204062174720.

The previous prime is 1221112002217. The next prime is 1221112002241. The reversal of 1221112002221 is 1222002111221.

It is a cyclic number.

It is not a de Polignac number, because 1221112002221 - 2² = 1221112002217 is a prime.

It is a super-2 number, since 2×1221112002221² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221112002221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221112002241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55095740 + ... + 55117898.

It is an arithmetic number, because the mean of its divisors is an integer number (77392093680).

Almost surely, 2^{1221112002221} is an apocalyptic number.

It is an amenable number.

1221112002221 is a deficient number, since it is larger than the sum of its proper divisors (17161496659).

1221112002221 is a wasteful number, since it uses less digits than its factorization.

1221112002221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24644.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 1221112002221 its reverse (1222002111221), we get a palindrome (2443114113442).

The spelling of 1221112002221 in words is "one trillion, two hundred twenty-one billion, one hundred twelve million, two thousand, two hundred twenty-one".