66118603840 has 56 divisors (see below), whose sum is σ = 157481378712. Its totient is φ = 26441318400.

The previous prime is 66118603787. The next prime is 66118603843. The reversal of 66118603840 is 4830681166.

It is a happy number.

66118603840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 24364096 + 66094239744 = 4936^2 + 257088^2 .

It is not an unprimeable number, because it can be changed into a prime (66118603843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1514802 + ... + 1557838.

It is an arithmetic number, because the mean of its divisors is an integer number (2812167477).

Almost surely, 2^66118603840 is an apocalyptic number.

It is an amenable number.

66118603840 is an abundant number, since it is smaller than the sum of its proper divisors (91362774872).

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

66118603840 is a wasteful number, since it uses less digits than its factorization.

66118603840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47855 (or 47845 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 43.

The spelling of 66118603840 in words is "sixty-six billion, one hundred eighteen million, six hundred three thousand, eight hundred forty".