81593584393 has 2 divisors, whose sum is σ = 81593584394. Its totient is φ = 81593584392.

The previous prime is 81593584367. The next prime is 81593584409. The reversal of 81593584393 is 39348539518.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65125508809 + 16468075584 = 255197^2 + 128328^2 .

It is a cyclic number.

It is not a de Polignac number, because 81593584393 - 2⁵ = 81593584361 is a prime.

It is a super-2 number, since 2×81593584393² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81593584993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40796792196 + 40796792197.

It is an arithmetic number, because the mean of its divisors is an integer number (40796792197).

Almost surely, 2^81593584393 is an apocalyptic number.

It is an amenable number.

81593584393 is a deficient number, since it is larger than the sum of its proper divisors (1).

81593584393 is an equidigital number, since it uses as much as digits as its factorization.

81593584393 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13996800, while the sum is 58.

The spelling of 81593584393 in words is "eighty-one billion, five hundred ninety-three million, five hundred eighty-four thousand, three hundred ninety-three".