78108387173 has 4 divisors (see below), whose sum is σ = 78211569420. Its totient is φ = 78005204928.

The previous prime is 78108387163. The next prime is 78108387191. The reversal of 78108387173 is 37178380187.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24958312324 + 53150074849 = 157982^2 + 230543^2 .

It is a cyclic number.

It is not a de Polignac number, because 78108387173 - 2²⁶ = 78041278309 is a prime.

It is a super-2 number, since 2×78108387173² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78108387163) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51589988 + ... + 51591501.

It is an arithmetic number, because the mean of its divisors is an integer number (19552892355).

Almost surely, 2^78108387173 is an apocalyptic number.

It is an amenable number.

78108387173 is a deficient number, since it is larger than the sum of its proper divisors (103182247).

78108387173 is a wasteful number, since it uses less digits than its factorization.

78108387173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103182246.

The product of its (nonzero) digits is 1580544, while the sum is 53.

The spelling of 78108387173 in words is "seventy-eight billion, one hundred eight million, three hundred eighty-seven thousand, one hundred seventy-three".