78865128 has 24 divisors (see below), whose sum is σ = 213593250. Its totient is φ = 26288352.

The previous prime is 78865121. The next prime is 78865153. The reversal of 78865128 is 82156887.

It can be written as a sum of positive squares in only one way, i.e., 66879684 + 11985444 = 8178^2 + 3462^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is not an unprimeable number, because it can be changed into a prime (78865121) 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 5 ways as a sum of consecutive naturals, for example, 547603 + ... + 547746.

Almost surely, 2^78865128 is an apocalyptic number.

It is an amenable number.

78865128 is an abundant number, since it is smaller than the sum of its proper divisors (134728122).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78865128 is a wasteful number, since it uses less digits than its factorization.

78865128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1095361 (or 1095354 counting only the distinct ones).

The product of its digits is 215040, while the sum is 45.

The square root of 78865128 is about 8880.6040335103. The cubic root of 78865128 is about 428.8397203914.

The spelling of 78865128 in words is "seventy-eight million, eight hundred sixty-five thousand, one hundred twenty-eight".