6659520491 has 4 divisors (see below), whose sum is σ = 7171791312. Its totient is φ = 6147249672.

The previous prime is 6659520481. The next prime is 6659520493. The reversal of 6659520491 is 1940259566.

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

It is a cyclic number.

It is not a de Polignac number, because 6659520491 - 2¹⁰ = 6659519467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6659520493) 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 3 ways as a sum of consecutive naturals, for example, 256135391 + ... + 256135416.

It is an arithmetic number, because the mean of its divisors is an integer number (1792947828).

Almost surely, 2^6659520491 is an apocalyptic number.

6659520491 is a deficient number, since it is larger than the sum of its proper divisors (512270821).

6659520491 is a wasteful number, since it uses less digits than its factorization.

6659520491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512270820.

The product of its (nonzero) digits is 583200, while the sum is 47.

The square root of 6659520491 is about 81605.8851492955. The cubic root of 6659520491 is about 1881.3993364584.

The spelling of 6659520491 in words is "six billion, six hundred fifty-nine million, five hundred twenty thousand, four hundred ninety-one".