78388871 has 16 divisors (see below), whose sum is σ = 88408320. Its totient is φ = 68886720.

The previous prime is 78388859. The next prime is 78388873. The reversal of 78388871 is 17888387.

It is a cyclic number.

It is not a de Polignac number, because 78388871 - 2¹⁰ = 78387847 is a prime.

It is a super-2 number, since 2×78388871² = 12289630193309282, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78388873) 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 15 ways as a sum of consecutive naturals, for example, 47915 + ... + 49523.

It is an arithmetic number, because the mean of its divisors is an integer number (5525520).

Almost surely, 2^78388871 is an apocalyptic number.

78388871 is a deficient number, since it is larger than the sum of its proper divisors (10019449).

78388871 is a wasteful number, since it uses less digits than its factorization.

78388871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1766.

The product of its digits is 602112, while the sum is 50.

The square root of 78388871 is about 8853.7489799519. The cubic root of 78388871 is about 427.9747397530.

The spelling of 78388871 in words is "seventy-eight million, three hundred eighty-eight thousand, eight hundred seventy-one".