66506368 has 16 divisors (see below), whose sum is σ = 132493410. Its totient is φ = 33253120.

The previous prime is 66506359. The next prime is 66506369. The reversal of 66506368 is 86360566.

It can be written as a sum of positive squares in only one way, i.e., 45050944 + 21455424 = 6712^2 + 4632^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a self number, because there is not a number n which added to its sum of digits gives 66506368.

It is not an unprimeable number, because it can be changed into a prime (66506369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 259663 + ... + 259918.

Almost surely, 2^66506368 is an apocalyptic number.

It is an amenable number.

66506368 is a deficient number, since it is larger than the sum of its proper divisors (65987042).

66506368 is an equidigital number, since it uses as much as digits as its factorization.

66506368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519595 (or 519583 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 40.

The square root of 66506368 is about 8155.1436529346. The cubic root of 66506368 is about 405.1548825893.

The spelling of 66506368 in words is "sixty-six million, five hundred six thousand, three hundred sixty-eight".