6516478997 has 4 divisors (see below), whose sum is σ = 7447404576. Its totient is φ = 5585553420.

The previous prime is 6516478967. The next prime is 6516479009. The reversal of 6516478997 is 7998746156.

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 6516478997 - 2⁸ = 6516478741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6516478937) 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, 465462779 + ... + 465462792.

It is an arithmetic number, because the mean of its divisors is an integer number (1861851144).

Almost surely, 2^6516478997 is an apocalyptic number.

It is an amenable number.

6516478997 is a deficient number, since it is larger than the sum of its proper divisors (930925579).

6516478997 is an equidigital number, since it uses as much as digits as its factorization.

6516478997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 930925578.

The product of its digits is 22861440, while the sum is 62.

The square root of 6516478997 is about 80724.7111918030. The cubic root of 6516478997 is about 1867.8313767221.

The spelling of 6516478997 in words is "six billion, five hundred sixteen million, four hundred seventy-eight thousand, nine hundred ninety-seven".