6821686125 has 24 divisors (see below), whose sum is σ = 12297228216. Its totient is φ = 3638232000.

The previous prime is 6821686097. The next prime is 6821686129. The reversal of 6821686125 is 5216861286.

6821686125 is a `hidden beast` number, since 6 + 8 + 21 + 6 + 8 + 612 + 5 = 666.

6821686125 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 752185476 + 6069500649 = 27426^2 + 77907^2 .

It is not a de Polignac number, because 6821686125 - 2⁶ = 6821686061 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6821686129) 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 23 ways as a sum of consecutive naturals, for example, 3030736 + ... + 3032985.

It is an arithmetic number, because the mean of its divisors is an integer number (512384509).

Almost surely, 2^6821686125 is an apocalyptic number.

It is an amenable number.

6821686125 is a deficient number, since it is larger than the sum of its proper divisors (5475542091).

6821686125 is a wasteful number, since it uses less digits than its factorization.

6821686125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6063742 (or 6063729 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 6821686125 is about 82593.4992901984. The cubic root of 6821686125 is about 1896.5483153833.

The spelling of 6821686125 in words is "six billion, eight hundred twenty-one million, six hundred eighty-six thousand, one hundred twenty-five".