66666605550501 has 8 divisors (see below), whose sum is σ = 96969608073504. Its totient is φ = 40404003363920.

The previous prime is 66666605550487. The next prime is 66666605550509. The reversal of 66666605550501 is 10505550666666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66666605550501 - 2⁵ = 66666605550469 is a prime.

It is a super-3 number, since 3×66666605550501³ (a number of 42 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66666605550509) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1010100084066 + ... + 1010100084131.

It is an arithmetic number, because the mean of its divisors is an integer number (12121201009188).

Almost surely, 2^{66666605550501} is an apocalyptic number.

It is an amenable number.

66666605550501 is a deficient number, since it is larger than the sum of its proper divisors (30303002523003).

66666605550501 is a wasteful number, since it uses less digits than its factorization.

66666605550501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2020200168211.

The product of its (nonzero) digits is 29160000, while the sum is 57.

The spelling of 66666605550501 in words is "sixty-six trillion, six hundred sixty-six billion, six hundred five million, five hundred fifty thousand, five hundred one".