78317538 has 32 divisors (see below), whose sum is σ = 178609536. Its totient is φ = 22679808.

The previous prime is 78317531. The next prime is 78317543. The reversal of 78317538 is 83571387.

It is a super-2 number, since 2×78317538² = 12267273516762888, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 78317538.

It is not an unprimeable number, because it can be changed into a prime (78317531) 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, 28206 + ... + 30857.

It is an arithmetic number, because the mean of its divisors is an integer number (5581548).

Almost surely, 2^78317538 is an apocalyptic number.

78317538 is a gapful number since it is divisible by the number (78) formed by its first and last digit.

78317538 is an abundant number, since it is smaller than the sum of its proper divisors (100291998).

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

78317538 is a wasteful number, since it uses less digits than its factorization.

78317538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59098.

The product of its digits is 141120, while the sum is 42.

The square root of 78317538 is about 8849.7196565767. The cubic root of 78317538 is about 427.8448829392.

The spelling of 78317538 in words is "seventy-eight million, three hundred seventeen thousand, five hundred thirty-eight".