66178736725 has 6 divisors (see below), whose sum is σ = 82061633570. Its totient is φ = 52942989360.

The previous prime is 66178736711. The next prime is 66178736731. The reversal of 66178736725 is 52763787166.

It can be written as a sum of positive squares in 3 ways, for example, as 14605689316 + 51573047409 = 120854^2 + 227097^2 .

It is not a de Polignac number, because 66178736725 - 2¹³ = 66178728533 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66178736725.

It is a congruent number.

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 5 ways as a sum of consecutive naturals, for example, 1323574710 + ... + 1323574759.

Almost surely, 2^66178736725 is an apocalyptic number.

It is an amenable number.

66178736725 is a deficient number, since it is larger than the sum of its proper divisors (15882896845).

66178736725 is a wasteful number, since it uses less digits than its factorization.

66178736725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2647149479 (or 2647149474 counting only the distinct ones).

The product of its digits is 17781120, while the sum is 58.

The spelling of 66178736725 in words is "sixty-six billion, one hundred seventy-eight million, seven hundred thirty-six thousand, seven hundred twenty-five".