64665755671 has 4 divisors (see below), whose sum is σ = 70544460744. Its totient is φ = 58787050600.

The previous prime is 64665755659. The next prime is 64665755681. The reversal of 64665755671 is 17655756646.

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

It is a cyclic number.

It is not a de Polignac number, because 64665755671 - 2⁷ = 64665755543 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 (64665755681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2939352520 + ... + 2939352541.

It is an arithmetic number, because the mean of its divisors is an integer number (17636115186).

Almost surely, 2^64665755671 is an apocalyptic number.

64665755671 is a deficient number, since it is larger than the sum of its proper divisors (5878705073).

64665755671 is a wasteful number, since it uses less digits than its factorization.

64665755671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5878705072.

The product of its digits is 31752000, while the sum is 58.

The spelling of 64665755671 in words is "sixty-four billion, six hundred sixty-five million, seven hundred fifty-five thousand, six hundred seventy-one".