81447104723 has 2 divisors, whose sum is σ = 81447104724. Its totient is φ = 81447104722.

The previous prime is 81447104719. The next prime is 81447104803. The reversal of 81447104723 is 32740174418.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81447104723 - 2² = 81447104719 is a prime.

It is not a weakly prime, because it can be changed into another prime (81447104923) 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, 40723552361 + 40723552362.

It is an arithmetic number, because the mean of its divisors is an integer number (40723552362).

Almost surely, 2^81447104723 is an apocalyptic number.

81447104723 is a deficient number, since it is larger than the sum of its proper divisors (1).

81447104723 is an equidigital number, since it uses as much as digits as its factorization.

81447104723 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 150528, while the sum is 41.

The spelling of 81447104723 in words is "eighty-one billion, four hundred forty-seven million, one hundred four thousand, seven hundred twenty-three".