78346966517 has 2 divisors, whose sum is σ = 78346966518. Its totient is φ = 78346966516.

The previous prime is 78346966421. The next prime is 78346966519. The reversal of 78346966517 is 71566964387.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74357654596 + 3989311921 = 272686^2 + 63161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78346966517 is a prime.

It is a super-2 number, since 2×78346966517² (a number of 23 digits) contains 22 as substring.

Together with 78346966519, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78346966517.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78346966519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39173483258 + 39173483259.

It is an arithmetic number, because the mean of its divisors is an integer number (39173483259).

Almost surely, 2^78346966517 is an apocalyptic number.

It is an amenable number.

78346966517 is a deficient number, since it is larger than the sum of its proper divisors (1).

78346966517 is an equidigital number, since it uses as much as digits as its factorization.

78346966517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45722880, while the sum is 62.

The spelling of 78346966517 in words is "seventy-eight billion, three hundred forty-six million, nine hundred sixty-six thousand, five hundred seventeen".