81744672754873 has 2 divisors, whose sum is σ = 81744672754874. Its totient is φ = 81744672754872.

The previous prime is 81744672754861. The next prime is 81744672754967. The reversal of 81744672754873 is 37845727644718.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77866735069369 + 3877937685504 = 8824213^2 + 1969248^2 .

It is a cyclic number.

It is not a de Polignac number, because 81744672754873 - 2²¹ = 81744670657721 is a prime.

It is a super-2 number, since 2×81744672754873² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81744672754796 and 81744672754805.

It is not a weakly prime, because it can be changed into another prime (81744672755873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40872336377436 + 40872336377437.

It is an arithmetic number, because the mean of its divisors is an integer number (40872336377437).

Almost surely, 2^{81744672754873} is an apocalyptic number.

It is an amenable number.

81744672754873 is a deficient number, since it is larger than the sum of its proper divisors (1).

81744672754873 is an equidigital number, since it uses as much as digits as its factorization.

81744672754873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1770209280, while the sum is 73.

The spelling of 81744672754873 in words is "eighty-one trillion, seven hundred forty-four billion, six hundred seventy-two million, seven hundred fifty-four thousand, eight hundred seventy-three".