66278013725 has 72 divisors (see below), whose sum is σ = 104655989088. Its totient is φ = 41172700800.

The previous prime is 66278013691. The next prime is 66278013731. The reversal of 66278013725 is 52731087266.

It is not a de Polignac number, because 66278013725 - 2²⁸ = 66009578269 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 66278013725.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 3939782 + ... + 3956568.

It is an arithmetic number, because the mean of its divisors is an integer number (1453555404).

Almost surely, 2^66278013725 is an apocalyptic number.

It is an amenable number.

66278013725 is a deficient number, since it is larger than the sum of its proper divisors (38377975363).

66278013725 is a wasteful number, since it uses less digits than its factorization.

66278013725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17115 (or 17103 counting only the distinct ones).

The product of its (nonzero) digits is 846720, while the sum is 47.

The spelling of 66278013725 in words is "sixty-six billion, two hundred seventy-eight million, thirteen thousand, seven hundred twenty-five".