66448357812 has 18 divisors (see below), whose sum is σ = 167966682338. Its totient is φ = 22149452592.

The previous prime is 66448357763. The next prime is 66448357813. The reversal of 66448357812 is 21875384466.

It is a happy number.

66448357812 is a `hidden beast` number, since 6 + 64 + 4 + 8 + 3 + 578 + 1 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 64082897316 + 2365460496 = 253146^2 + 48636^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66448357813) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 922893823 + ... + 922893894.

Almost surely, 2^66448357812 is an apocalyptic number.

It is an amenable number.

66448357812 is an abundant number, since it is smaller than the sum of its proper divisors (101518324526).

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

66448357812 is a wasteful number, since it uses less digits than its factorization.

66448357812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1845787727 (or 1845787722 counting only the distinct ones).

The product of its digits is 7741440, while the sum is 54.

The spelling of 66448357812 in words is "sixty-six billion, four hundred forty-eight million, three hundred fifty-seven thousand, eight hundred twelve".