78166288687 has 2 divisors, whose sum is σ = 78166288688. Its totient is φ = 78166288686.

The previous prime is 78166288679. The next prime is 78166288729. The reversal of 78166288687 is 78688266187.

It is a weak prime.

It is an emirp because it is prime and its reverse (78688266187) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78166288687 - 2³ = 78166288679 is a prime.

It is a super-2 number, since 2×78166288687² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78166288657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39083144343 + 39083144344.

It is an arithmetic number, because the mean of its divisors is an integer number (39083144344).

Almost surely, 2^78166288687 is an apocalyptic number.

78166288687 is a deficient number, since it is larger than the sum of its proper divisors (1).

78166288687 is an equidigital number, since it uses as much as digits as its factorization.

78166288687 is an evil number, because the sum of its binary digits is even.

The product of its digits is 86704128, while the sum is 67.

The spelling of 78166288687 in words is "seventy-eight billion, one hundred sixty-six million, two hundred eighty-eight thousand, six hundred eighty-seven".