66580555508567 has 4 divisors (see below), whose sum is σ = 66614716903800. Its totient is φ = 66546394113336.

The previous prime is 66580555508563. The next prime is 66580555508573. The reversal of 66580555508567 is 76580555508566.

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 66580555508567 - 2² = 66580555508563 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66580555508567.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66580555508563) 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, 17080694693 + ... + 17080698590.

It is an arithmetic number, because the mean of its divisors is an integer number (16653679225950).

Almost surely, 2^{66580555508567} is an apocalyptic number.

66580555508567 is a deficient number, since it is larger than the sum of its proper divisors (34161395233).

66580555508567 is a wasteful number, since it uses less digits than its factorization.

66580555508567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34161395232.

The product of its (nonzero) digits is 1512000000, while the sum is 71.

Subtracting 66580555508567 from its reverse (76580555508566), we obtain a palindrome (9999999999999).

The spelling of 66580555508567 in words is "sixty-six trillion, five hundred eighty billion, five hundred fifty-five million, five hundred eight thousand, five hundred sixty-seven".