66688888888999 has 16 divisors (see below), whose sum is σ = 73165798339200. Its totient is φ = 60408113773536.

The previous prime is 66688888888969. The next prime is 66688888889011. The reversal of 66688888888999 is 99988888888666.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 66688888888999 - 2²⁹ = 66688352018087 is a prime.

66688888888999 is a strobogrammatic number because it is the same when read upside-down.

It is a Duffinian number.

It is a plaindrome in base 10.

It is a zygodrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 66688888888895 and 66688888888904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66688888888939) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76786389 + ... + 77650030.

It is an arithmetic number, because the mean of its divisors is an integer number (4572862396200).

Almost surely, 2^{66688888888999} is an apocalyptic number.

66688888888999 is a deficient number, since it is larger than the sum of its proper divisors (6476909450201).

66688888888999 is a wasteful number, since it uses less digits than its factorization.

66688888888999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154437054.

The product of its digits is 2641807540224, while the sum is 109.

The spelling of 66688888888999 in words is "sixty-six trillion, six hundred eighty-eight billion, eight hundred eighty-eight million, eight hundred eighty-eight thousand, nine hundred ninety-nine".