5178817060861 has 2 divisors, whose sum is σ = 5178817060862. Its totient is φ = 5178817060860.

The previous prime is 5178817060831. The next prime is 5178817060873. The reversal of 5178817060861 is 1680607188715.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3396258295236 + 1782558765625 = 1842894^2 + 1335125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5178817060861 is a prime.

It is a super-2 number, since 2×5178817060861² (a number of 26 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 5178817060796 and 5178817060805.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5178817060831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2589408530430 + 2589408530431.

It is an arithmetic number, because the mean of its divisors is an integer number (2589408530431).

Almost surely, 2^{5178817060861} is an apocalyptic number.

It is an amenable number.

5178817060861 is a deficient number, since it is larger than the sum of its proper divisors (1).

5178817060861 is an equidigital number, since it uses as much as digits as its factorization.

5178817060861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4515840, while the sum is 58.

The spelling of 5178817060861 in words is "five trillion, one hundred seventy-eight billion, eight hundred seventeen million, sixty thousand, eight hundred sixty-one".