6516647993 has 4 divisors (see below), whose sum is σ = 6518245008. Its totient is φ = 6515050980.

The previous prime is 6516647989. The next prime is 6516648031. The reversal of 6516647993 is 3997466156.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6516647993 - 2² = 6516647989 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6516647393) 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 3 ways as a sum of consecutive naturals, for example, 792371 + ... + 800552.

It is an arithmetic number, because the mean of its divisors is an integer number (1629561252).

Almost surely, 2^6516647993 is an apocalyptic number.

It is an amenable number.

6516647993 is a deficient number, since it is larger than the sum of its proper divisors (1597015).

6516647993 is a wasteful number, since it uses less digits than its factorization.

6516647993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1597014.

The product of its digits is 7348320, while the sum is 56.

The square root of 6516647993 is about 80725.7579276900. The cubic root of 6516647993 is about 1867.8475231361.

The spelling of 6516647993 in words is "six billion, five hundred sixteen million, six hundred forty-seven thousand, nine hundred ninety-three".