221020111123 has 4 divisors (see below), whose sum is σ = 252594412720. Its totient is φ = 189445809528.

The previous prime is 221020110979. The next prime is 221020111157. The reversal of 221020111123 is 321111020122.

221020111123 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 221020111123 - 2¹³ = 221020102931 is a prime.

It is a super-2 number, since 2×221020111123² (a number of 23 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 = 221020111097 and 221020111106.

It is not an unprimeable number, because it can be changed into a prime (221020111423) 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, 15787150788 + ... + 15787150801.

It is an arithmetic number, because the mean of its divisors is an integer number (63148603180).

Almost surely, 2^221020111123 is an apocalyptic number.

221020111123 is a deficient number, since it is larger than the sum of its proper divisors (31574301597).

221020111123 is an equidigital number, since it uses as much as digits as its factorization.

221020111123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31574301596.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 221020111123 its reverse (321111020122), we get a palindrome (542131131245).

The spelling of 221020111123 in words is "two hundred twenty-one billion, twenty million, one hundred eleven thousand, one hundred twenty-three".