205128025715729 has 2 divisors, whose sum is σ = 205128025715730. Its totient is φ = 205128025715728.

The previous prime is 205128025715659. The next prime is 205128025715737. The reversal of 205128025715729 is 927517520821502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 205083737355025 + 44288360704 = 14320745^2 + 210448^2 .

It is a cyclic number.

It is not a de Polignac number, because 205128025715729 - 2¹⁶ = 205128025650193 is a prime.

It is not a weakly prime, because it can be changed into another prime (205128025715749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102564012857864 + 102564012857865.

It is an arithmetic number, because the mean of its divisors is an integer number (102564012857865).

Almost surely, 2^{205128025715729} is an apocalyptic number.

It is an amenable number.

205128025715729 is a deficient number, since it is larger than the sum of its proper divisors (1).

205128025715729 is an equidigital number, since it uses as much as digits as its factorization.

205128025715729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7056000, while the sum is 56.

The spelling of 205128025715729 in words is "two hundred five trillion, one hundred twenty-eight billion, twenty-five million, seven hundred fifteen thousand, seven hundred twenty-nine".