666888888999 has 16 divisors (see below), whose sum is σ = 913662350432. Its totient is φ = 432365724288.

The previous prime is 666888888997. The next prime is 666888889061. The reversal of 666888888999 is 999888888666.

It is not a de Polignac number, because 666888888999 - 2¹ = 666888888997 is a prime.

666888888999 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 congruent number.

It is not an unprimeable number, because it can be changed into a prime (666888888997) 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, 1235344 + ... + 1691109.

It is an arithmetic number, because the mean of its divisors is an integer number (57103896902).

Almost surely, 2^666888888999 is an apocalyptic number.

666888888999 is a deficient number, since it is larger than the sum of its proper divisors (246773461433).

666888888999 is a wasteful number, since it uses less digits than its factorization.

666888888999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2928546.

The product of its digits is 41278242816, while the sum is 93.

The spelling of 666888888999 in words is "six hundred sixty-six billion, eight hundred eighty-eight million, eight hundred eighty-eight thousand, nine hundred ninety-nine".