66515648807200 has 144 divisors (see below), whose sum is σ = 162614785050144. Its totient is φ = 26568029030400.

The previous prime is 66515648807183. The next prime is 66515648807213. The reversal of 66515648807200 is 270884651566.

It is a happy 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, 2227046667 + ... + 2227076533.

It is an arithmetic number, because the mean of its divisors is an integer number (1129269340626).

Almost surely, 2^{66515648807200} 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 66515648807200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81307392525072).

66515648807200 is an abundant number, since it is smaller than the sum of its proper divisors (96099136242944).

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

66515648807200 is a wasteful number, since it uses less digits than its factorization.

66515648807200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33795 (or 33782 counting only the distinct ones).

The product of its (nonzero) digits is 19353600, while the sum is 58.

The spelling of 66515648807200 in words is "sixty-six trillion, five hundred fifteen billion, six hundred forty-eight million, eight hundred seven thousand, two hundred".