6821742131 has 2 divisors, whose sum is σ = 6821742132. Its totient is φ = 6821742130.

The previous prime is 6821742127. The next prime is 6821742157. The reversal of 6821742131 is 1312471286.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6821742131 - 2² = 6821742127 is a prime.

It is a super-2 number, since 2×6821742131² = 93072331403720842322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 6821742091 and 6821742100.

It is not a weakly prime, because it can be changed into another prime (6821742331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3410871065 + 3410871066.

It is an arithmetic number, because the mean of its divisors is an integer number (3410871066).

Almost surely, 2^6821742131 is an apocalyptic number.

6821742131 is a deficient number, since it is larger than the sum of its proper divisors (1).

6821742131 is an equidigital number, since it uses as much as digits as its factorization.

6821742131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16128, while the sum is 35.

The square root of 6821742131 is about 82593.8383355562. The cubic root of 6821742131 is about 1896.5535055857.

The spelling of 6821742131 in words is "six billion, eight hundred twenty-one million, seven hundred forty-two thousand, one hundred thirty-one".