6921875 has 14 divisors (see below), whose sum is σ = 8671764. Its totient is φ = 5525000.

The previous prime is 6921869. The next prime is 6921877. The reversal of 6921875 is 5781296.

It is not a de Polignac number, because 6921875 - 2¹⁴ = 6905491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6921877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 15404 + ... + 15846.

Almost surely, 2^6921875 is an apocalyptic number.

6921875 is a deficient number, since it is larger than the sum of its proper divisors (1749889).

6921875 is an frugal number, since it uses more digits than its factorization.

6921875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 473 (or 448 counting only the distinct ones).

The product of its digits is 30240, while the sum is 38.

The square root of 6921875 is about 2630.9456474811. The cubic root of 6921875 is about 190.5787982628.

The spelling of 6921875 in words is "six million, nine hundred twenty-one thousand, eight hundred seventy-five".