66544818 has 16 divisors (see below), whose sum is σ = 133573440. Its totient is φ = 22100976.

The previous prime is 66544801. The next prime is 66544843. The reversal of 66544818 is 81844566.

It is a self number, because there is not a number n which added to its sum of digits gives 66544818.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18358 + ... + 21681.

It is an arithmetic number, because the mean of its divisors is an integer number (8348340).

Almost surely, 2^66544818 is an apocalyptic number.

66544818 is an abundant number, since it is smaller than the sum of its proper divisors (67028622).

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

66544818 is a wasteful number, since it uses less digits than its factorization.

66544818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40321.

The product of its digits is 184320, while the sum is 42.

The square root of 66544818 is about 8157.5007201961. The cubic root of 66544818 is about 405.2329463123.

The spelling of 66544818 in words is "sixty-six million, five hundred forty-four thousand, eight hundred eighteen".