20440123 has 16 divisors (see below), whose sum is σ = 23452416. Its totient is φ = 17633440.

The previous prime is 20440111. The next prime is 20440151. The reversal of 20440123 is 32104402.

It is a de Polignac number, because none of the positive numbers 2^k-20440123 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20440097 and 20440106.

It is not an unprimeable number, because it can be changed into a prime (20440153) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43536 + ... + 44002.

It is an arithmetic number, because the mean of its divisors is an integer number (1465776).

Almost surely, 2^20440123 is an apocalyptic number.

20440123 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

20440123 is a deficient number, since it is larger than the sum of its proper divisors (3012293).

20440123 is a wasteful number, since it uses less digits than its factorization.

20440123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 674.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 20440123 is about 4521.0754251616. The cubic root of 20440123 is about 273.4184613226.

Adding to 20440123 its reverse (32104402), we get a palindrome (52544525).

The spelling of 20440123 in words is "twenty million, four hundred forty thousand, one hundred twenty-three".