63440728717 has 2 divisors, whose sum is σ = 63440728718. Its totient is φ = 63440728716.

The previous prime is 63440728711. The next prime is 63440728739. The reversal of 63440728717 is 71782704436.

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., 63088378276 + 352350441 = 251174^2 + 18771^2 .

It is a cyclic number.

It is not a de Polignac number, because 63440728717 - 2²³ = 63432340109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (63440728711) 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 as a sum of consecutive naturals, namely, 31720364358 + 31720364359.

It is an arithmetic number, because the mean of its divisors is an integer number (31720364359).

Almost surely, 2^63440728717 is an apocalyptic number.

It is an amenable number.

63440728717 is a deficient number, since it is larger than the sum of its proper divisors (1).

63440728717 is an equidigital number, since it uses as much as digits as its factorization.

63440728717 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1580544, while the sum is 49.

The spelling of 63440728717 in words is "sixty-three billion, four hundred forty million, seven hundred twenty-eight thousand, seven hundred seventeen".