81592539473 has 2 divisors, whose sum is σ = 81592539474. Its totient is φ = 81592539472.

The previous prime is 81592539461. The next prime is 81592539529. The reversal of 81592539473 is 37493529518.

It is an a-pointer prime, because the next prime (81592539529) can be obtained adding 81592539473 to its sum of digits (56).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52676217169 + 28916322304 = 229513^2 + 170048^2 .

It is a cyclic number.

It is not a de Polignac number, because 81592539473 - 2³⁰ = 80518797649 is a prime.

It is not a weakly prime, because it can be changed into another prime (81592539403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40796269736 + 40796269737.

It is an arithmetic number, because the mean of its divisors is an integer number (40796269737).

Almost surely, 2^81592539473 is an apocalyptic number.

It is an amenable number.

81592539473 is a deficient number, since it is larger than the sum of its proper divisors (1).

81592539473 is an equidigital number, since it uses as much as digits as its factorization.

81592539473 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8164800, while the sum is 56.

The spelling of 81592539473 in words is "eighty-one billion, five hundred ninety-two million, five hundred thirty-nine thousand, four hundred seventy-three".