6731663521 has 16 divisors (see below), whose sum is σ = 7431096960. Its totient is φ = 6047009280.

The previous prime is 6731663513. The next prime is 6731663563. The reversal of 6731663521 is 1253661376.

It is a cyclic number.

It is not a de Polignac number, because 6731663521 - 2³ = 6731663513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6731663581) 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 15 ways as a sum of consecutive naturals, for example, 717700 + ... + 727018.

It is an arithmetic number, because the mean of its divisors is an integer number (464443560).

Almost surely, 2^6731663521 is an apocalyptic number.

It is an amenable number.

6731663521 is a deficient number, since it is larger than the sum of its proper divisors (699433439).

6731663521 is a wasteful number, since it uses less digits than its factorization.

6731663521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10104.

The product of its digits is 136080, while the sum is 40.

The square root of 6731663521 is about 82046.7154796583. The cubic root of 6731663521 is about 1888.1687254387.

The spelling of 6731663521 in words is "six billion, seven hundred thirty-one million, six hundred sixty-three thousand, five hundred twenty-one".