79721308685023 has 2 divisors, whose sum is σ = 79721308685024. Its totient is φ = 79721308685022.

The previous prime is 79721308684981. The next prime is 79721308685069. The reversal of 79721308685023 is 32058680312797.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 79721308685023 - 2¹⁷ = 79721308553951 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79721318685023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39860654342511 + 39860654342512.

It is an arithmetic number, because the mean of its divisors is an integer number (39860654342512).

Almost surely, 2^{79721308685023} is an apocalyptic number.

79721308685023 is a deficient number, since it is larger than the sum of its proper divisors (1).

79721308685023 is an equidigital number, since it uses as much as digits as its factorization.

79721308685023 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30481920, while the sum is 61.

The spelling of 79721308685023 in words is "seventy-nine trillion, seven hundred twenty-one billion, three hundred eight million, six hundred eighty-five thousand, twenty-three".