6491516639 has 2 divisors, whose sum is σ = 6491516640. Its totient is φ = 6491516638.

The previous prime is 6491516587. The next prime is 6491516651. The reversal of 6491516639 is 9366151946.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6491516639 - 2¹⁶ = 6491451103 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6491516539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3245758319 + 3245758320.

It is an arithmetic number, because the mean of its divisors is an integer number (3245758320).

Almost surely, 2^6491516639 is an apocalyptic number.

6491516639 is a deficient number, since it is larger than the sum of its proper divisors (1).

6491516639 is an equidigital number, since it uses as much as digits as its factorization.

6491516639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1049760, while the sum is 50.

The square root of 6491516639 is about 80569.9487340038. The cubic root of 6491516639 is about 1865.4433213594.

The spelling of 6491516639 in words is "six billion, four hundred ninety-one million, five hundred sixteen thousand, six hundred thirty-nine".