66918678 has 8 divisors (see below), whose sum is σ = 133837368. Its totient is φ = 22306224.

The previous prime is 66918673. The next prime is 66918721. The reversal of 66918678 is 87681966.

It is a happy number.

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

66918678 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 66918678.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66918671) 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, 5576551 + ... + 5576562.

It is an arithmetic number, because the mean of its divisors is an integer number (16729671).

Almost surely, 2^66918678 is an apocalyptic number.

66918678 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66918678 is a wasteful number, since it uses less digits than its factorization.

66918678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11153118.

The product of its digits is 870912, while the sum is 51.

The square root of 66918678 is about 8180.3837318307. The cubic root of 66918678 is about 405.9904185335.

The spelling of 66918678 in words is "sixty-six million, nine hundred eighteen thousand, six hundred seventy-eight".