66306728 has 8 divisors (see below), whose sum is σ = 124325130. Its totient is φ = 33153360.

The previous prime is 66306719. The next prime is 66306733. The reversal of 66306728 is 82760366.

It can be written as a sum of positive squares in only one way, i.e., 62378404 + 3928324 = 7898^2 + 1982^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 66306691 and 66306700.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4144163 + ... + 4144178.

Almost surely, 2^66306728 is an apocalyptic number.

It is an amenable number.

66306728 is a deficient number, since it is larger than the sum of its proper divisors (58018402).

66306728 is a wasteful number, since it uses less digits than its factorization.

66306728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8288347 (or 8288343 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 38.

The square root of 66306728 is about 8142.8943257296. The cubic root of 66306728 is about 404.7490758845.

The spelling of 66306728 in words is "sixty-six million, three hundred six thousand, seven hundred twenty-eight".