81672395489339 has 2 divisors, whose sum is σ = 81672395489340. Its totient is φ = 81672395489338.

The previous prime is 81672395489227. The next prime is 81672395489453. The reversal of 81672395489339 is 93398459327618.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81672395489339 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81672395489339.

It is not a weakly prime, because it can be changed into another prime (81672395389339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40836197744669 + 40836197744670.

It is an arithmetic number, because the mean of its divisors is an integer number (40836197744670).

Almost surely, 2^{81672395489339} is an apocalyptic number.

81672395489339 is a deficient number, since it is larger than the sum of its proper divisors (1).

81672395489339 is an equidigital number, since it uses as much as digits as its factorization.

81672395489339 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2116316160, while the sum is 77.

The spelling of 81672395489339 in words is "eighty-one trillion, six hundred seventy-two billion, three hundred ninety-five million, four hundred eighty-nine thousand, three hundred thirty-nine".