6399367081 has 2 divisors, whose sum is σ = 6399367082. Its totient is φ = 6399367080.

The previous prime is 6399367057. The next prime is 6399367127. The reversal of 6399367081 is 1807639936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5192499481 + 1206867600 = 72059^2 + 34740^2 .

It is a cyclic number.

It is not a de Polignac number, because 6399367081 - 2¹¹ = 6399365033 is a prime.

It is a super-2 number, since 2×6399367081² = 81903798074772921122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6399767081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3199683540 + 3199683541.

It is an arithmetic number, because the mean of its divisors is an integer number (3199683541).

Almost surely, 2^6399367081 is an apocalyptic number.

It is an amenable number.

6399367081 is a deficient number, since it is larger than the sum of its proper divisors (1).

6399367081 is an equidigital number, since it uses as much as digits as its factorization.

6399367081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1469664, while the sum is 52.

The square root of 6399367081 is about 79996.0441584457. The cubic root of 6399367081 is about 1856.5743283074.

The spelling of 6399367081 in words is "six billion, three hundred ninety-nine million, three hundred sixty-seven thousand, eighty-one".