78446887 has 4 divisors (see below), whose sum is σ = 78792696. Its totient is φ = 78101080.

The previous prime is 78446873. The next prime is 78446897. The reversal of 78446887 is 78864487.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78446887 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 (78446867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172564 + ... + 173017.

It is an arithmetic number, because the mean of its divisors is an integer number (19698174).

Almost surely, 2^78446887 is an apocalyptic number.

78446887 is a deficient number, since it is larger than the sum of its proper divisors (345809).

78446887 is a wasteful number, since it uses less digits than its factorization.

78446887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345808.

The product of its digits is 2408448, while the sum is 52.

The square root of 78446887 is about 8857.0247261707. The cubic root of 78446887 is about 428.0802958064.

The spelling of 78446887 in words is "seventy-eight million, four hundred forty-six thousand, eight hundred eighty-seven".