66723216 has 80 divisors (see below), whose sum is σ = 197904000. Its totient is φ = 18975744.

The previous prime is 66723179. The next prime is 66723233. The reversal of 66723216 is 61232766.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116980 + ... + 117548.

It is an arithmetic number, because the mean of its divisors is an integer number (2473800).

Almost surely, 2^66723216 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 66723216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98952000).

66723216 is an abundant number, since it is smaller than the sum of its proper divisors (131180784).

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

66723216 is a wasteful number, since it uses less digits than its factorization.

66723216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 936 (or 930 counting only the distinct ones).

The product of its digits is 18144, while the sum is 33.

The square root of 66723216 is about 8168.4280005396. The cubic root of 66723216 is about 405.5947487931.

The spelling of 66723216 in words is "sixty-six million, seven hundred twenty-three thousand, two hundred sixteen".