81651056713 has 2 divisors, whose sum is σ = 81651056714. Its totient is φ = 81651056712.

The previous prime is 81651056701. The next prime is 81651056717. The reversal of 81651056713 is 31765015618.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65023470009 + 16627586704 = 254997^2 + 128948^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81651056713 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81651056713.

It is not a weakly prime, because it can be changed into another prime (81651056717) 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, 40825528356 + 40825528357.

It is an arithmetic number, because the mean of its divisors is an integer number (40825528357).

Almost surely, 2^81651056713 is an apocalyptic number.

It is an amenable number.

81651056713 is a deficient number, since it is larger than the sum of its proper divisors (1).

81651056713 is an equidigital number, since it uses as much as digits as its factorization.

81651056713 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 151200, while the sum is 43.

The spelling of 81651056713 in words is "eighty-one billion, six hundred fifty-one million, fifty-six thousand, seven hundred thirteen".