20123443123 has 4 divisors (see below), whose sum is σ = 22998220720. Its totient is φ = 17248665528.

The previous prime is 20123443121. The next prime is 20123443127. The reversal of 20123443123 is 32134432102.

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 20123443123 - 2¹ = 20123443121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20123443121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1437388788 + ... + 1437388801.

It is an arithmetic number, because the mean of its divisors is an integer number (5749555180).

Almost surely, 2^20123443123 is an apocalyptic number.

20123443123 is a deficient number, since it is larger than the sum of its proper divisors (2874777597).

20123443123 is an equidigital number, since it uses as much as digits as its factorization.

20123443123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2874777596.

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 20123443123 its reverse (32134432102), we get a palindrome (52257875225).

The spelling of 20123443123 in words is "twenty billion, one hundred twenty-three million, four hundred forty-three thousand, one hundred twenty-three".