17728745729 has 2 divisors, whose sum is σ = 17728745730. Its totient is φ = 17728745728.

The previous prime is 17728745719. The next prime is 17728745773. The reversal of 17728745729 is 92754782771.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15687061504 + 2041684225 = 125248^2 + 45185^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-17728745729 is a prime.

It is not a weakly prime, because it can be changed into another prime (17728745719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8864372864 + 8864372865.

It is an arithmetic number, because the mean of its divisors is an integer number (8864372865).

Almost surely, 2^17728745729 is an apocalyptic number.

It is an amenable number.

17728745729 is a deficient number, since it is larger than the sum of its proper divisors (1).

17728745729 is an equidigital number, since it uses as much as digits as its factorization.

17728745729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13829760, while the sum is 59.

The spelling of 17728745729 in words is "seventeen billion, seven hundred twenty-eight million, seven hundred forty-five thousand, seven hundred twenty-nine".