6440791831 has 2 divisors, whose sum is σ = 6440791832. Its totient is φ = 6440791830.

The previous prime is 6440791813. The next prime is 6440791843. The reversal of 6440791831 is 1381970446.

Together with previous prime (6440791813) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6440791831 - 2⁹ = 6440791319 is a prime.

It is a super-2 number, since 2×6440791831² = 82967598820552665122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6440791871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3220395915 + 3220395916.

It is an arithmetic number, because the mean of its divisors is an integer number (3220395916).

Almost surely, 2^6440791831 is an apocalyptic number.

6440791831 is a deficient number, since it is larger than the sum of its proper divisors (1).

6440791831 is an equidigital number, since it uses as much as digits as its factorization.

6440791831 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 6440791831 is about 80254.5439897331. The cubic root of 6440791831 is about 1860.5717430499.

The spelling of 6440791831 in words is "six billion, four hundred forty million, seven hundred ninety-one thousand, eight hundred thirty-one".