221110122121121 has 4 divisors (see below), whose sum is σ = 223138655351700. Its totient is φ = 219081588890544.

The previous prime is 221110122121103. The next prime is 221110122121171. The reversal of 221110122121121 is 121121221011122.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 89027509122721 + 132082612998400 = 9435439^2 + 11492720^2 .

It is a cyclic number.

It is not a de Polignac number, because 221110122121121 - 2¹⁴ = 221110122104737 is a prime.

It is a super-2 number, since 2×221110122121121² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221110122121093 and 221110122121102.

It is not an unprimeable number, because it can be changed into a prime (221110122121171) 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, 1014266615126 + ... + 1014266615343.

It is an arithmetic number, because the mean of its divisors is an integer number (55784663837925).

Almost surely, 2^{221110122121121} is an apocalyptic number.

It is an amenable number.

221110122121121 is a deficient number, since it is larger than the sum of its proper divisors (2028533230579).

221110122121121 is a wasteful number, since it uses less digits than its factorization.

221110122121121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2028533230578.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 221110122121121 its reverse (121121221011122), we get a palindrome (342231343132243).

The spelling of 221110122121121 in words is "two hundred twenty-one trillion, one hundred ten billion, one hundred twenty-two million, one hundred twenty-one thousand, one hundred twenty-one".