66565216 has 24 divisors (see below), whose sum is σ = 133275240. Its totient is φ = 32717568.

The previous prime is 66565211. The next prime is 66565223. The reversal of 66565216 is 61256566.

It is a super-2 number, since 2×66565216² = 8861855962253312, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66565211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15741 + ... + 19516.

It is an arithmetic number, because the mean of its divisors is an integer number (5553135).

Almost surely, 2^66565216 is an apocalyptic number.

It is an amenable number.

66565216 is an abundant number, since it is smaller than the sum of its proper divisors (66710024).

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

66565216 is a wasteful number, since it uses less digits than its factorization.

66565216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35326 (or 35318 counting only the distinct ones).

The product of its digits is 64800, while the sum is 37.

The square root of 66565216 is about 8158.7508847862. The cubic root of 66565216 is about 405.2743474684.

The spelling of 66565216 in words is "sixty-six million, five hundred sixty-five thousand, two hundred sixteen".