221110001001221 has 4 divisors (see below), whose sum is σ = 221950723438752. Its totient is φ = 220269278563692.

The previous prime is 221110001001199. The next prime is 221110001001257. The reversal of 221110001001221 is 122100100011122.

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 221110001001221 - 2¹⁰ = 221110001000197 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221110001001196 and 221110001001205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221110001001121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 420361218371 + ... + 420361218896.

It is an arithmetic number, because the mean of its divisors is an integer number (55487680859688).

Almost surely, 2^{221110001001221} is an apocalyptic number.

It is an amenable number.

221110001001221 is a deficient number, since it is larger than the sum of its proper divisors (840722437531).

221110001001221 is an equidigital number, since it uses as much as digits as its factorization.

221110001001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 840722437530.

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

Adding to 221110001001221 its reverse (122100100011122), we get a palindrome (343210101012343).

Subtracting from 221110001001221 its reverse (122100100011122), we obtain a palindrome (99009900990099).

The spelling of 221110001001221 in words is "two hundred twenty-one trillion, one hundred ten billion, one million, one thousand, two hundred twenty-one".