6884138521 has 4 divisors (see below), whose sum is σ = 7413687652. Its totient is φ = 6354589392.

The previous prime is 6884138507. The next prime is 6884138531. The reversal of 6884138521 is 1258314886.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3518862400 + 3365276121 = 59320^2 + 58011^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6884138521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6884138531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 264774546 + ... + 264774571.

It is an arithmetic number, because the mean of its divisors is an integer number (1853421913).

Almost surely, 2^6884138521 is an apocalyptic number.

It is an amenable number.

6884138521 is a deficient number, since it is larger than the sum of its proper divisors (529549131).

6884138521 is a wasteful number, since it uses less digits than its factorization.

6884138521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529549130.

The product of its digits is 368640, while the sum is 46.

The square root of 6884138521 is about 82970.7088134120. The cubic root of 6884138521 is about 1902.3183630782.

The spelling of 6884138521 in words is "six billion, eight hundred eighty-four million, one hundred thirty-eight thousand, five hundred twenty-one".