66066013520 has 40 divisors (see below), whose sum is σ = 165419136456. Its totient is φ = 24393604608.

The previous prime is 66066013493. The next prime is 66066013567. The reversal of 66066013520 is 2531066066.

It can be written as a sum of positive squares in 4 ways, for example, as 281971264 + 65784042256 = 16792^2 + 256484^2 .

It is a tau number, because it is divible by the number of its divisors (40).

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, 31761467 + ... + 31763546.

Almost surely, 2^66066013520 is an apocalyptic number.

It is an amenable number.

66066013520 is an abundant number, since it is smaller than the sum of its proper divisors (99353122936).

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

66066013520 is a wasteful number, since it uses less digits than its factorization.

66066013520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63525039 (or 63525033 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 35.

Adding to 66066013520 its reverse (2531066066), we get a palindrome (68597079586).

The spelling of 66066013520 in words is "sixty-six billion, sixty-six million, thirteen thousand, five hundred twenty".