20121000123 has 16 divisors (see below), whose sum is σ = 30964144896. Its totient is φ = 11383874400.

The previous prime is 20121000113. The next prime is 20121000161. The reversal of 20121000123 is 32100012102.

It is not a de Polignac number, because 20121000123 - 2⁵ = 20121000091 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20121000099 and 20121000108.

It is not an unprimeable number, because it can be changed into a prime (20121000103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4741161 + ... + 4745402.

It is an arithmetic number, because the mean of its divisors is an integer number (1935259056).

Almost surely, 2^20121000123 is an apocalyptic number.

20121000123 is a deficient number, since it is larger than the sum of its proper divisors (10843144773).

20121000123 is a wasteful number, since it uses less digits than its factorization.

20121000123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9486674.

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 20121000123 its reverse (32100012102), we get a palindrome (52221012225).

The spelling of 20121000123 in words is "twenty billion, one hundred twenty-one million, one hundred twenty-three", and thus it is an aban number.