78173 has 2 divisors, whose sum is σ = 78174. Its totient is φ = 78172.

The previous prime is 78167. The next prime is 78179. The reversal of 78173 is 37187.

It is a balanced prime because it is at equal distance from previous prime (78167) and next prime (78179).

It can be written as a sum of positive squares in only one way, i.e., 76729 + 1444 = 277^2 + 38^2 .

It is a cyclic number.

It is not a de Polignac number, because 78173 - 2⁴ = 78157 is a prime.

It is a super-2 number, since 2×78173² = 12222035858, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39086 + 39087.

It is an arithmetic number, because the mean of its divisors is an integer number (39087).

2⁷⁸¹⁷³ is an apocalyptic number.

It is an amenable number.

78173 is a deficient number, since it is larger than the sum of its proper divisors (1).

78173 is an equidigital number, since it uses as much as digits as its factorization.

78173 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1176, while the sum is 26.

The square root of 78173 is about 279.5943490130. The cubic root of 78173 is about 42.7581519513.

The spelling of 78173 in words is "seventy-eight thousand, one hundred seventy-three".