66523216 has 40 divisors (see below), whose sum is σ = 134053920. Its totient is φ = 31941504.

The previous prime is 66523207. The next prime is 66523231. The reversal of 66523216 is 61232566.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 142215 + ... + 142681.

It is an arithmetic number, because the mean of its divisors is an integer number (3351348).

Almost surely, 2^66523216 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 66523216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67026960).

66523216 is an abundant number, since it is smaller than the sum of its proper divisors (67530704).

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

66523216 is a wasteful number, since it uses less digits than its factorization.

66523216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 811 (or 805 counting only the distinct ones).

The product of its digits is 12960, while the sum is 31.

The square root of 66523216 is about 8156.1765552249. The cubic root of 66523216 is about 405.1890922113.

The spelling of 66523216 in words is "sixty-six million, five hundred twenty-three thousand, two hundred sixteen".