66166520 has 64 divisors (see below), whose sum is σ = 172730880. Its totient is φ = 22340736.

The previous prime is 66166501. The next prime is 66166523. The reversal of 66166520 is 2566166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66166523) by changing a digit.

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, 16997 + ... + 20523.

It is an arithmetic number, because the mean of its divisors is an integer number (2698920).

Almost surely, 2^66166520 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 66166520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86365440).

66166520 is an abundant number, since it is smaller than the sum of its proper divisors (106564360).

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

66166520 is a wasteful number, since it uses less digits than its factorization.

66166520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3612 (or 3608 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 66166520 is about 8134.2805459364. The cubic root of 66166520 is about 404.4635889939.

The spelling of 66166520 in words is "sixty-six million, one hundred sixty-six thousand, five hundred twenty".