66723918 has 8 divisors (see below), whose sum is σ = 133447848. Its totient is φ = 22241304.

The previous prime is 66723911. The next prime is 66723941. The reversal of 66723918 is 81932766.

It is a happy number.

66723918 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

66723918 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 66723918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66723911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5560321 + ... + 5560332.

It is an arithmetic number, because the mean of its divisors is an integer number (16680981).

Almost surely, 2^66723918 is an apocalyptic number.

66723918 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.

66723918 is a wasteful number, since it uses less digits than its factorization.

66723918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11120658.

The product of its digits is 108864, while the sum is 42.

The square root of 66723918 is about 8168.4709707509. The cubic root of 66723918 is about 405.5961712191.

The spelling of 66723918 in words is "sixty-six million, seven hundred twenty-three thousand, nine hundred eighteen".