64471878545 has 4 divisors (see below), whose sum is σ = 77366254260. Its totient is φ = 51577502832.

The previous prime is 64471878539. The next prime is 64471878577. The reversal of 64471878545 is 54587817446.

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 33582761536 + 30889117009 = 183256^2 + 175753^2 .

It is a cyclic number.

It is not a de Polignac number, because 64471878545 - 2⁴ = 64471878529 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6447187850 + ... + 6447187859.

It is an arithmetic number, because the mean of its divisors is an integer number (19341563565).

Almost surely, 2^64471878545 is an apocalyptic number.

It is an amenable number.

64471878545 is a deficient number, since it is larger than the sum of its proper divisors (12894375715).

64471878545 is a wasteful number, since it uses less digits than its factorization.

64471878545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12894375714.

The product of its digits is 30105600, while the sum is 59.

The spelling of 64471878545 in words is "sixty-four billion, four hundred seventy-one million, eight hundred seventy-eight thousand, five hundred forty-five".