64788243991 has 12 divisors (see below), whose sum is σ = 67116389184. Its totient is φ = 62538291200.

The previous prime is 64788243983. The next prime is 64788244013. The reversal of 64788243991 is 19934288746.

It is not a de Polignac number, because 64788243991 - 2³ = 64788243983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64788243901) 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 in 11 ways as a sum of consecutive naturals, for example, 4594071 + ... + 4608151.

It is an arithmetic number, because the mean of its divisors is an integer number (5593032432).

Almost surely, 2^64788243991 is an apocalyptic number.

64788243991 is a deficient number, since it is larger than the sum of its proper divisors (2328145193).

64788243991 is a wasteful number, since it uses less digits than its factorization.

64788243991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19610 (or 19581 counting only the distinct ones).

The product of its digits is 20901888, while the sum is 61.

The spelling of 64788243991 in words is "sixty-four billion, seven hundred eighty-eight million, two hundred forty-three thousand, nine hundred ninety-one".