66538841886 has 48 divisors (see below), whose sum is σ = 161524282608. Its totient is φ = 19618329600.

The previous prime is 66538841851. The next prime is 66538841899. The reversal of 66538841886 is 68814883566.

66538841886 is a `hidden beast` number, since 6 + 6 + 538 + 8 + 4 + 18 + 86 = 666.

It is a congruent 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, 4533955 + ... + 4548606.

It is an arithmetic number, because the mean of its divisors is an integer number (3365089221).

Almost surely, 2^66538841886 is an apocalyptic number.

66538841886 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

66538841886 is an abundant number, since it is smaller than the sum of its proper divisors (94985440722).

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

66538841886 is a wasteful number, since it uses less digits than its factorization.

66538841886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9082617 (or 9082614 counting only the distinct ones).

The product of its digits is 53084160, while the sum is 63.

The spelling of 66538841886 in words is "sixty-six billion, five hundred thirty-eight million, eight hundred forty-one thousand, eight hundred eighty-six".