20120123105 has 4 divisors (see below), whose sum is σ = 24144147732. Its totient is φ = 16096098480.

The previous prime is 20120123071. The next prime is 20120123113. The reversal of 20120123105 is 50132102102.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13856350369 + 6263772736 = 117713^2 + 79144^2 .

It is not a de Polignac number, because 20120123105 - 2⁸ = 20120122849 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 2012012306 + ... + 2012012315.

It is an arithmetic number, because the mean of its divisors is an integer number (6036036933).

Almost surely, 2^20120123105 is an apocalyptic number.

It is an amenable number.

20120123105 is a deficient number, since it is larger than the sum of its proper divisors (4024024627).

20120123105 is an equidigital number, since it uses as much as digits as its factorization.

20120123105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4024024626.

The product of its (nonzero) digits is 120, while the sum is 17.

Adding to 20120123105 its reverse (50132102102), we get a palindrome (70252225207).

The spelling of 20120123105 in words is "twenty billion, one hundred twenty million, one hundred twenty-three thousand, one hundred five".