78388869 has 8 divisors (see below), whose sum is σ = 112558432. Its totient is φ = 48239280.

The previous prime is 78388859. The next prime is 78388873. The reversal of 78388869 is 96888387.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78388869 - 2⁵ = 78388837 is a prime.

It is a super-2 number, since 2×78388869² = 12289629566198322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78388859) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1004947 + ... + 1005024.

It is an arithmetic number, because the mean of its divisors is an integer number (14069804).

Almost surely, 2^78388869 is an apocalyptic number.

It is an amenable number.

78388869 is a deficient number, since it is larger than the sum of its proper divisors (34169563).

78388869 is a wasteful number, since it uses less digits than its factorization.

78388869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2009987.

The product of its digits is 4644864, while the sum is 57.

The square root of 78388869 is about 8853.7488670054. The cubic root of 78388869 is about 427.9747361132.

The spelling of 78388869 in words is "seventy-eight million, three hundred eighty-eight thousand, eight hundred sixty-nine".