81598529 has 2 divisors, whose sum is σ = 81598530. Its totient is φ = 81598528.

The previous prime is 81598523. The next prime is 81598537. The reversal of 81598529 is 92589518.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70174129 + 11424400 = 8377^2 + 3380^2 .

It is a cyclic number.

It is not a de Polignac number, because 81598529 - 2⁴ = 81598513 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (81598523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40799264 + 40799265.

It is an arithmetic number, because the mean of its divisors is an integer number (40799265).

Almost surely, 2^81598529 is an apocalyptic number.

It is an amenable number.

81598529 is a deficient number, since it is larger than the sum of its proper divisors (1).

81598529 is an equidigital number, since it uses as much as digits as its factorization.

81598529 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 259200, while the sum is 47.

The square root of 81598529 is about 9033.1904109235. The cubic root of 81598529 is about 433.7379706929.

The spelling of 81598529 in words is "eighty-one million, five hundred ninety-eight thousand, five hundred twenty-nine".