64840449717 has 12 divisors (see below), whose sum is σ = 99167746860. Its totient is φ = 40684203648.

The previous prime is 64840449689. The next prime is 64840449743. The reversal of 64840449717 is 71794404846.

64840449717 is a `hidden beast` number, since 64 + 84 + 0 + 4 + 497 + 17 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 48135921201 + 16704528516 = 219399^2 + 129246^2 .

It is not a de Polignac number, because 64840449717 - 2²⁰ = 64839401141 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64840449757) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 211896742 + ... + 211897047.

It is an arithmetic number, because the mean of its divisors is an integer number (8263978905).

Almost surely, 2^64840449717 is an apocalyptic number.

It is an amenable number.

64840449717 is a deficient number, since it is larger than the sum of its proper divisors (34327297143).

64840449717 is a wasteful number, since it uses less digits than its factorization.

64840449717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 423793812 (or 423793809 counting only the distinct ones).

The product of its (nonzero) digits is 5419008, while the sum is 54.

The spelling of 64840449717 in words is "sixty-four billion, eight hundred forty million, four hundred forty-nine thousand, seven hundred seventeen".