66505208 has 64 divisors (see below), whose sum is σ = 157075200. Its totient is φ = 25643520.

The previous prime is 66505181. The next prime is 66505217. The reversal of 66505208 is 80250566.

It is a happy number.

It is a super-2 number, since 2×66505208² = 8845885382246528, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65408 + ... + 66416.

It is an arithmetic number, because the mean of its divisors is an integer number (2454300).

Almost surely, 2^66505208 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66505208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78537600).

66505208 is an abundant number, since it is smaller than the sum of its proper divisors (90569992).

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

66505208 is a wasteful number, since it uses less digits than its factorization.

66505208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1140 (or 1136 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 66505208 is about 8155.0725318663. The cubic root of 66505208 is about 405.1525270134.

The spelling of 66505208 in words is "sixty-six million, five hundred five thousand, two hundred eight".