66144067655 has 4 divisors (see below), whose sum is σ = 79372881192. Its totient is φ = 52915254120.

The previous prime is 66144067607. The next prime is 66144067669. The reversal of 66144067655 is 55676044166.

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

It is not a de Polignac number, because 66144067655 - 2¹⁴ = 66144051271 is a prime.

It is a Duffinian number.

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, 6614406761 + ... + 6614406770.

It is an arithmetic number, because the mean of its divisors is an integer number (19843220298).

Almost surely, 2^66144067655 is an apocalyptic number.

66144067655 is a deficient number, since it is larger than the sum of its proper divisors (13228813537).

66144067655 is a wasteful number, since it uses less digits than its factorization.

66144067655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13228813536.

The product of its (nonzero) digits is 3628800, while the sum is 50.

The spelling of 66144067655 in words is "sixty-six billion, one hundred forty-four million, sixty-seven thousand, six hundred fifty-five".