123440023 has 4 divisors (see below), whose sum is σ = 141074320. Its totient is φ = 105805728.

The previous prime is 123439999. The next prime is 123440033. The reversal of 123440023 is 320044321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 320044321 = 911 ⋅351311.

It is a de Polignac number, because none of the positive numbers 2^k-123440023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123440033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8817138 + ... + 8817151.

It is an arithmetic number, because the mean of its divisors is an integer number (35268580).

Almost surely, 2^123440023 is an apocalyptic number.

123440023 is a deficient number, since it is larger than the sum of its proper divisors (17634297).

123440023 is an equidigital number, since it uses as much as digits as its factorization.

123440023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17634296.

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 123440023 is about 11110.3565649353. The cubic root of 123440023 is about 497.9113176280.

Adding to 123440023 its reverse (320044321), we get a palindrome (443484344).

The spelling of 123440023 in words is "one hundred twenty-three million, four hundred forty thousand, twenty-three".