81598894523 has 2 divisors, whose sum is σ = 81598894524. Its totient is φ = 81598894522.

The previous prime is 81598894511. The next prime is 81598894561. The reversal of 81598894523 is 32549889518.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81598894523 - 2⁶ = 81598894459 is a prime.

It is not a weakly prime, because it can be changed into another prime (81598894423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40799447261 + 40799447262.

It is an arithmetic number, because the mean of its divisors is an integer number (40799447262).

Almost surely, 2^81598894523 is an apocalyptic number.

81598894523 is a deficient number, since it is larger than the sum of its proper divisors (1).

81598894523 is an equidigital number, since it uses as much as digits as its factorization.

81598894523 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24883200, while the sum is 62.

The spelling of 81598894523 in words is "eighty-one billion, five hundred ninety-eight million, eight hundred ninety-four thousand, five hundred twenty-three".