78424771 has 4 divisors (see below), whose sum is σ = 78761592. Its totient is φ = 78087952.

The previous prime is 78424763. The next prime is 78424813. The reversal of 78424771 is 17742487.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17742487 = 7 ⋅2534641.

It is a cyclic number.

It is not a de Polignac number, because 78424771 - 2³ = 78424763 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78424721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 168061 + ... + 168526.

It is an arithmetic number, because the mean of its divisors is an integer number (19690398).

Almost surely, 2^78424771 is an apocalyptic number.

78424771 is a deficient number, since it is larger than the sum of its proper divisors (336821).

78424771 is a wasteful number, since it uses less digits than its factorization.

78424771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336820.

The product of its digits is 87808, while the sum is 40.

The square root of 78424771 is about 8855.7761376403. The cubic root of 78424771 is about 428.0400634317.

The spelling of 78424771 in words is "seventy-eight million, four hundred twenty-four thousand, seven hundred seventy-one".