81079384717 has 2 divisors, whose sum is σ = 81079384718. Its totient is φ = 81079384716.

The previous prime is 81079384691. The next prime is 81079384753. The reversal of 81079384717 is 71748397018.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52352185636 + 28727199081 = 228806^2 + 169491^2 .

It is a cyclic number.

It is not a de Polignac number, because 81079384717 - 2²³ = 81070996109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81079384777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40539692358 + 40539692359.

It is an arithmetic number, because the mean of its divisors is an integer number (40539692359).

Almost surely, 2^81079384717 is an apocalyptic number.

It is an amenable number.

81079384717 is a deficient number, since it is larger than the sum of its proper divisors (1).

81079384717 is an equidigital number, since it uses as much as digits as its factorization.

81079384717 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2370816, while the sum is 55.

The spelling of 81079384717 in words is "eighty-one billion, seventy-nine million, three hundred eighty-four thousand, seven hundred seventeen".