20542573123889 has 2 divisors, whose sum is σ = 20542573123890. Its totient is φ = 20542573123888.

The previous prime is 20542573123843. The next prime is 20542573123901. The reversal of 20542573123889 is 98832137524502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17345700643489 + 3196872480400 = 4164817^2 + 1787980^2 .

It is a cyclic number.

It is not a de Polignac number, because 20542573123889 - 2²⁰ = 20542572075313 is a prime.

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 (20542573123819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10271286561944 + 10271286561945.

It is an arithmetic number, because the mean of its divisors is an integer number (10271286561945).

Almost surely, 2^{20542573123889} is an apocalyptic number.

It is an amenable number.

20542573123889 is a deficient number, since it is larger than the sum of its proper divisors (1).

20542573123889 is an equidigital number, since it uses as much as digits as its factorization.

20542573123889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 29030400, while the sum is 59.

The spelling of 20542573123889 in words is "twenty trillion, five hundred forty-two billion, five hundred seventy-three million, one hundred twenty-three thousand, eight hundred eighty-nine".