78591171 has 4 divisors (see below), whose sum is σ = 104788232. Its totient is φ = 52394112.

The previous prime is 78591167. The next prime is 78591173. The reversal of 78591171 is 17119587.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17119587 = 3 ⋅5706529.

It is not a de Polignac number, because 78591171 - 2² = 78591167 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78591173) 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, 13098526 + ... + 13098531.

It is an arithmetic number, because the mean of its divisors is an integer number (26197058).

Almost surely, 2^78591171 is an apocalyptic number.

78591171 is a deficient number, since it is larger than the sum of its proper divisors (26197061).

78591171 is a wasteful number, since it uses less digits than its factorization.

78591171 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26197060.

The product of its digits is 17640, while the sum is 39.

The square root of 78591171 is about 8865.1661574953. The cubic root of 78591171 is about 428.3425849852.

The spelling of 78591171 in words is "seventy-eight million, five hundred ninety-one thousand, one hundred seventy-one".