64678422487645 has 4 divisors (see below), whose sum is σ = 77614106985180. Its totient is φ = 51742737990112.

The previous prime is 64678422487621. The next prime is 64678422487691. The reversal of 64678422487645 is 54678422487646.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10393518314404 + 54284904173241 = 3223898^2 + 7367829^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64678422487645 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6467842248760 + ... + 6467842248769.

It is an arithmetic number, because the mean of its divisors is an integer number (19403526746295).

Almost surely, 2^{64678422487645} is an apocalyptic number.

It is an amenable number.

64678422487645 is a deficient number, since it is larger than the sum of its proper divisors (12935684497535).

64678422487645 is a wasteful number, since it uses less digits than its factorization.

64678422487645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12935684497534.

The product of its digits is 3468165120, while the sum is 73.

Subtracting from 64678422487645 its reverse (54678422487646), we obtain a palindrome (9999999999999).

The spelling of 64678422487645 in words is "sixty-four trillion, six hundred seventy-eight billion, four hundred twenty-two million, four hundred eighty-seven thousand, six hundred forty-five".