79803944557 has 2 divisors, whose sum is σ = 79803944558. Its totient is φ = 79803944556.

The previous prime is 79803944513. The next prime is 79803944567. The reversal of 79803944557 is 75544930897.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78919417476 + 884527081 = 280926^2 + 29741^2 .

It is a cyclic number.

It is not a de Polignac number, because 79803944557 - 2¹⁹ = 79803420269 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 79803944495 and 79803944504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79803944567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39901972278 + 39901972279.

It is an arithmetic number, because the mean of its divisors is an integer number (39901972279).

Almost surely, 2^79803944557 is an apocalyptic number.

It is an amenable number.

79803944557 is a deficient number, since it is larger than the sum of its proper divisors (1).

79803944557 is an equidigital number, since it uses as much as digits as its factorization.

79803944557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38102400, while the sum is 61.

The spelling of 79803944557 in words is "seventy-nine billion, eight hundred three million, nine hundred forty-four thousand, five hundred fifty-seven".