66338728 has 16 divisors (see below), whose sum is σ = 130932000. Its totient is φ = 31423536.

The previous prime is 66338717. The next prime is 66338771. The reversal of 66338728 is 82783366.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 218068 + ... + 218371.

It is an arithmetic number, because the mean of its divisors is an integer number (8183250).

Almost surely, 2^66338728 is an apocalyptic number.

It is an amenable number.

66338728 is a deficient number, since it is larger than the sum of its proper divisors (64593272).

66338728 is a wasteful number, since it uses less digits than its factorization.

66338728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436464 (or 436460 counting only the distinct ones).

The product of its digits is 290304, while the sum is 43.

The square root of 66338728 is about 8144.8589920268. The cubic root of 66338728 is about 404.8141768067.

The spelling of 66338728 in words is "sixty-six million, three hundred thirty-eight thousand, seven hundred twenty-eight".