66487713831 has 72 divisors (see below), whose sum is σ = 121940726544. Its totient is φ = 34520048640.

The previous prime is 66487713793. The next prime is 66487713833. The reversal of 66487713831 is 13831778466.

66487713831 is a `hidden beast` number, since 66 + 487 + 71 + 3 + 8 + 31 = 666.

It is not a de Polignac number, because 66487713831 - 2⁶ = 66487713767 is a prime.

It is a super-2 number, since 2×66487713831² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66487713833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 14730231 + ... + 14734743.

It is an arithmetic number, because the mean of its divisors is an integer number (1693621202).

Almost surely, 2^66487713831 is an apocalyptic number.

66487713831 is a deficient number, since it is larger than the sum of its proper divisors (55453012713).

66487713831 is a wasteful number, since it uses less digits than its factorization.

66487713831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7581 (or 7571 counting only the distinct ones).

The product of its digits is 4064256, while the sum is 54.

The spelling of 66487713831 in words is "sixty-six billion, four hundred eighty-seven million, seven hundred thirteen thousand, eight hundred thirty-one".