81180076613 has 2 divisors, whose sum is σ = 81180076614. Its totient is φ = 81180076612.

The previous prime is 81180076577. The next prime is 81180076643. The reversal of 81180076613 is 31667008118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65389138369 + 15790938244 = 255713^2 + 125662^2 .

It is a cyclic number.

It is not a de Polignac number, because 81180076613 - 2²⁸ = 80911641157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81180076643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40590038306 + 40590038307.

It is an arithmetic number, because the mean of its divisors is an integer number (40590038307).

Almost surely, 2^81180076613 is an apocalyptic number.

It is an amenable number.

81180076613 is a deficient number, since it is larger than the sum of its proper divisors (1).

81180076613 is an equidigital number, since it uses as much as digits as its factorization.

81180076613 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 41.

The spelling of 81180076613 in words is "eighty-one billion, one hundred eighty million, seventy-six thousand, six hundred thirteen".