79890679017577 has 2 divisors, whose sum is σ = 79890679017578. Its totient is φ = 79890679017576.

The previous prime is 79890679017559. The next prime is 79890679017601. The reversal of 79890679017577 is 77571097609897.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44721639755776 + 35169039261801 = 6687424^2 + 5930349^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79890679017577 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 79890679017577.

It is not a weakly prime, because it can be changed into another prime (79890679017557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39945339508788 + 39945339508789.

It is an arithmetic number, because the mean of its divisors is an integer number (39945339508789).

Almost surely, 2^{79890679017577} is an apocalyptic number.

It is an amenable number.

79890679017577 is a deficient number, since it is larger than the sum of its proper divisors (1).

79890679017577 is an equidigital number, since it uses as much as digits as its factorization.

79890679017577 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2940552720, while the sum is 82.

The spelling of 79890679017577 in words is "seventy-nine trillion, eight hundred ninety billion, six hundred seventy-nine million, seventeen thousand, five hundred seventy-seven".