6516899989 has 2 divisors, whose sum is σ = 6516899990. Its totient is φ = 6516899988.

The previous prime is 6516899899. The next prime is 6516899993. The reversal of 6516899989 is 9899986156.

Together with previous prime (6516899899) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3970890225 + 2546009764 = 63015^2 + 50458^2 .

It is a cyclic number.

It is not a de Polignac number, because 6516899989 - 2²¹ = 6514802837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6516899489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3258449994 + 3258449995.

It is an arithmetic number, because the mean of its divisors is an integer number (3258449995).

Almost surely, 2^6516899989 is an apocalyptic number.

It is an amenable number.

6516899989 is a deficient number, since it is larger than the sum of its proper divisors (1).

6516899989 is an equidigital number, since it uses as much as digits as its factorization.

6516899989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75582720, while the sum is 70.

The square root of 6516899989 is about 80727.3187279251. The cubic root of 6516899989 is about 1867.8715991149.

The spelling of 6516899989 in words is "six billion, five hundred sixteen million, eight hundred ninety-nine thousand, nine hundred eighty-nine".