78771871 has 4 divisors (see below), whose sum is σ = 78876144. Its totient is φ = 78667600.

The previous prime is 78771839. The next prime is 78771881. The reversal of 78771871 is 17817787.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17817787 = 13 ⋅1370599.

It is a cyclic number.

It is not a de Polignac number, because 78771871 - 2⁵ = 78771839 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78771821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50995 + ... + 52516.

It is an arithmetic number, because the mean of its divisors is an integer number (19719036).

Almost surely, 2^78771871 is an apocalyptic number.

78771871 is a deficient number, since it is larger than the sum of its proper divisors (104273).

78771871 is a wasteful number, since it uses less digits than its factorization.

78771871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104272.

The product of its digits is 153664, while the sum is 46.

The square root of 78771871 is about 8875.3518803482. The cubic root of 78771871 is about 428.6706212359.

The spelling of 78771871 in words is "seventy-eight million, seven hundred seventy-one thousand, eight hundred seventy-one".