20105023 has 4 divisors (see below), whose sum is σ = 20648440. Its totient is φ = 19561608.

The previous prime is 20105009. The next prime is 20105039. The reversal of 20105023 is 32050102.

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 20105023 - 2¹³ = 20096831 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20104994 and 20105012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20105053) 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, 271653 + ... + 271726.

It is an arithmetic number, because the mean of its divisors is an integer number (5162110).

Almost surely, 2^20105023 is an apocalyptic number.

20105023 is a deficient number, since it is larger than the sum of its proper divisors (543417).

20105023 is an equidigital number, since it uses as much as digits as its factorization.

20105023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 543416.

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 20105023 is about 4483.8625090428. The cubic root of 20105023 is about 271.9160595582.

Adding to 20105023 its reverse (32050102), we get a palindrome (52155125).

The spelling of 20105023 in words is "twenty million, one hundred five thousand, twenty-three".