21220220110123 has 4 divisors (see below), whose sum is σ = 21226625250808. Its totient is φ = 21213814969440.

The previous prime is 21220220110099. The next prime is 21220220110163. The reversal of 21220220110123 is 32101102202212.

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 21220220110123 - 2²⁵ = 21220186555691 is a prime.

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 21220220110123.

It is not an unprimeable number, because it can be changed into a prime (21220220110163) 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, 3202565373 + ... + 3202571998.

It is an arithmetic number, because the mean of its divisors is an integer number (5306656312702).

Almost surely, 2^{21220220110123} is an apocalyptic number.

21220220110123 is a deficient number, since it is larger than the sum of its proper divisors (6405140685).

21220220110123 is an equidigital number, since it uses as much as digits as its factorization.

21220220110123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6405140684.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 21220220110123 its reverse (32101102202212), we get a palindrome (53321322312335).

The spelling of 21220220110123 in words is "twenty-one trillion, two hundred twenty billion, two hundred twenty million, one hundred ten thousand, one hundred twenty-three".