66516576 has 144 divisors (see below), whose sum is σ = 208196352. Its totient is φ = 18213120.

The previous prime is 66516559. The next prime is 66516581. The reversal of 66516576 is 67561566.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 645741 + ... + 645843.

It is an arithmetic number, because the mean of its divisors is an integer number (1445808).

Almost surely, 2^66516576 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 66516576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104098176).

66516576 is an abundant number, since it is smaller than the sum of its proper divisors (141679776).

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

66516576 is a wasteful number, since it uses less digits than its factorization.

66516576 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 146 counting only the distinct ones).

The product of its digits is 226800, while the sum is 42.

The square root of 66516576 is about 8155.7694915931. The cubic root of 66516576 is about 405.1756104764.

The spelling of 66516576 in words is "sixty-six million, five hundred sixteen thousand, five hundred seventy-six".