6349181681 has 2 divisors, whose sum is σ = 6349181682. Its totient is φ = 6349181680.

The previous prime is 6349181677. The next prime is 6349181687. The reversal of 6349181681 is 1861819436.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3975933025 + 2373248656 = 63055^2 + 48716^2 .

It is a cyclic number.

It is not a de Polignac number, because 6349181681 - 2² = 6349181677 is a prime.

It is a super-2 number, since 2×6349181681² = 80624216036691971522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6349181687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3174590840 + 3174590841.

It is an arithmetic number, because the mean of its divisors is an integer number (3174590841).

Almost surely, 2^6349181681 is an apocalyptic number.

It is an amenable number.

6349181681 is a deficient number, since it is larger than the sum of its proper divisors (1).

6349181681 is an equidigital number, since it uses as much as digits as its factorization.

6349181681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 47.

The square root of 6349181681 is about 79681.7524970429. The cubic root of 6349181681 is about 1851.7083495079.

The spelling of 6349181681 in words is "six billion, three hundred forty-nine million, one hundred eighty-one thousand, six hundred eighty-one".