20012120123081 has 2 divisors, whose sum is σ = 20012120123082. Its totient is φ = 20012120123080.

The previous prime is 20012120123027. The next prime is 20012120123089. The reversal of 20012120123081 is 18032102121002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13142038788025 + 6870081335056 = 3625195^2 + 2621084^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20012120123081 is a prime.

It is a super-2 number, since 2×20012120123081² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20012120123089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10006060061540 + 10006060061541.

It is an arithmetic number, because the mean of its divisors is an integer number (10006060061541).

Almost surely, 2^{20012120123081} is an apocalyptic number.

It is an amenable number.

20012120123081 is a deficient number, since it is larger than the sum of its proper divisors (1).

20012120123081 is an equidigital number, since it uses as much as digits as its factorization.

20012120123081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 384, while the sum is 23.

Adding to 20012120123081 its reverse (18032102121002), we get a palindrome (38044222244083).

The spelling of 20012120123081 in words is "twenty trillion, twelve billion, one hundred twenty million, one hundred twenty-three thousand, eighty-one".