66368742012520 has 64 divisors (see below), whose sum is σ = 149801832507600. Its totient is φ = 26463637217280.

The previous prime is 66368742012509. The next prime is 66368742012523. The reversal of 66368742012520 is 2521024786366.

It can be written as a sum of positive squares in 8 ways, for example, as 38860835951716 + 27507906060804 = 6233846^2 + 5244798^2 .

It is not an unprimeable number, because it can be changed into a prime (66368742012523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25148590 + ... + 27662050.

Almost surely, 2^{66368742012520} is an apocalyptic number.

It is an amenable number.

66368742012520 is an abundant number, since it is smaller than the sum of its proper divisors (83433090495080).

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

66368742012520 is a wasteful number, since it uses less digits than its factorization.

66368742012520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2515558 (or 2515554 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 52.

Adding to 66368742012520 its reverse (2521024786366), we get a palindrome (68889766798886).

The spelling of 66368742012520 in words is "sixty-six trillion, three hundred sixty-eight billion, seven hundred forty-two million, twelve thousand, five hundred twenty".