66518056 has 32 divisors (see below), whose sum is σ = 137206080. Its totient is φ = 30230640.

The previous prime is 66518009. The next prime is 66518057. The reversal of 66518056 is 65081566.

It is not an unprimeable number, because it can be changed into a prime (66518057) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7525 + ... + 13771.

It is an arithmetic number, because the mean of its divisors is an integer number (4287690).

Almost surely, 2^66518056 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 66518056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68603040).

66518056 is an abundant number, since it is smaller than the sum of its proper divisors (70688024).

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

66518056 is a wasteful number, since it uses less digits than its factorization.

66518056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6286 (or 6260 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 37.

The square root of 66518056 is about 8155.8602244031. The cubic root of 66518056 is about 405.1786155191.

It can be divided in two parts, 665 and 18056, that added together give a triangular number (18721 = T₁₉₃).

The spelling of 66518056 in words is "sixty-six million, five hundred eighteen thousand, fifty-six".