66631885794 has 40 divisors (see below), whose sum is σ = 149350839660. Its totient is φ = 22203777024.

The previous prime is 66631885787. The next prime is 66631885813. The reversal of 66631885794 is 49758813666.

It can be written as a sum of positive squares in 2 ways, for example, as 63254765025 + 3377120769 = 251505^2 + 58113^2 .

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 477522 + ... + 601074.

Almost surely, 2^66631885794 is an apocalyptic number.

66631885794 is an abundant number, since it is smaller than the sum of its proper divisors (82718953866).

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

66631885794 is a wasteful number, since it uses less digits than its factorization.

66631885794 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126896 (or 126887 counting only the distinct ones).

The product of its digits is 52254720, while the sum is 63.

The spelling of 66631885794 in words is "sixty-six billion, six hundred thirty-one million, eight hundred eighty-five thousand, seven hundred ninety-four".