6463991 has 2 divisors, whose sum is σ = 6463992. Its totient is φ = 6463990.

The previous prime is 6463979. The next prime is 6463999. The reversal of 6463991 is 1993646.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6463991 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6463999) 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 as a sum of consecutive naturals, namely, 3231995 + 3231996.

It is an arithmetic number, because the mean of its divisors is an integer number (3231996).

Almost surely, 2^6463991 is an apocalyptic number.

6463991 is a deficient number, since it is larger than the sum of its proper divisors (1).

6463991 is an equidigital number, since it uses as much as digits as its factorization.

6463991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34992, while the sum is 38.

The square root of 6463991 is about 2542.4380031773. The cubic root of 6463991 is about 186.2802938577.

The spelling of 6463991 in words is "six million, four hundred sixty-three thousand, nine hundred ninety-one".