20105123 has 8 divisors (see below), whose sum is σ = 20653248. Its totient is φ = 19560744.

The previous prime is 20105119. The next prime is 20105131. The reversal of 20105123 is 32150102.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20105123 - 2² = 20105119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20105098 and 20105107.

It is not an unprimeable number, because it can be changed into a prime (20405123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12440 + ... + 13962.

It is an arithmetic number, because the mean of its divisors is an integer number (2581656).

Almost surely, 2^20105123 is an apocalyptic number.

20105123 is a deficient number, since it is larger than the sum of its proper divisors (548125).

20105123 is a wasteful number, since it uses less digits than its factorization.

20105123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1873.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 20105123 is about 4483.8736601292. The cubic root of 20105123 is about 271.9165103835.

Adding to 20105123 its reverse (32150102), we get a palindrome (52255225).

The spelling of 20105123 in words is "twenty million, one hundred five thousand, one hundred twenty-three".