6811721725 has 6 divisors (see below), whose sum is σ = 8446534970. Its totient is φ = 5449377360.

The previous prime is 6811721713. The next prime is 6811721759. The reversal of 6811721725 is 5271271186.

It can be written as a sum of positive squares in 3 ways, for example, as 4481689 + 6807240036 = 2117^2 + 82506^2 .

It is not a de Polignac number, because 6811721725 - 2²¹ = 6809624573 is a prime.

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, 136234410 + ... + 136234459.

Almost surely, 2^6811721725 is an apocalyptic number.

It is an amenable number.

6811721725 is a deficient number, since it is larger than the sum of its proper divisors (1634813245).

6811721725 is a wasteful number, since it uses less digits than its factorization.

6811721725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272468879 (or 272468874 counting only the distinct ones).

The product of its digits is 47040, while the sum is 40.

The square root of 6811721725 is about 82533.1553074278. The cubic root of 6811721725 is about 1895.6244394507.

The spelling of 6811721725 in words is "six billion, eight hundred eleven million, seven hundred twenty-one thousand, seven hundred twenty-five".