78669317873 has 2 divisors, whose sum is σ = 78669317874. Its totient is φ = 78669317872.

The previous prime is 78669317869. The next prime is 78669317887. The reversal of 78669317873 is 37871396687.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49627363984 + 29041953889 = 222772^2 + 170417^2 .

It is an emirp because it is prime and its reverse (37871396687) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78669317873 - 2² = 78669317869 is a prime.

It is not a weakly prime, because it can be changed into another prime (78669317893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39334658936 + 39334658937.

It is an arithmetic number, because the mean of its divisors is an integer number (39334658937).

Almost surely, 2^78669317873 is an apocalyptic number.

It is an amenable number.

78669317873 is a deficient number, since it is larger than the sum of its proper divisors (1).

78669317873 is an equidigital number, since it uses as much as digits as its factorization.

78669317873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64012032, while the sum is 65.

The spelling of 78669317873 in words is "seventy-eight billion, six hundred sixty-nine million, three hundred seventeen thousand, eight hundred seventy-three".