81914976443 has 2 divisors, whose sum is σ = 81914976444. Its totient is φ = 81914976442.

The previous prime is 81914976439. The next prime is 81914976449. The reversal of 81914976443 is 34467941918.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81914976443 - 2² = 81914976439 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (81914976449) 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, 40957488221 + 40957488222.

It is an arithmetic number, because the mean of its divisors is an integer number (40957488222).

Almost surely, 2^81914976443 is an apocalyptic number.

81914976443 is a deficient number, since it is larger than the sum of its proper divisors (1).

81914976443 is an equidigital number, since it uses as much as digits as its factorization.

81914976443 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5225472, while the sum is 56.

The spelling of 81914976443 in words is "eighty-one billion, nine hundred fourteen million, nine hundred seventy-six thousand, four hundred forty-three".