78238907538 has 16 divisors (see below), whose sum is σ = 170703071136. Its totient is φ = 23708759840.

The previous prime is 78238907531. The next prime is 78238907581. The reversal of 78238907538 is 83570983287.

It is a super-2 number, since 2×78238907538² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78238907531) 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, 592718931 + ... + 592719062.

It is an arithmetic number, because the mean of its divisors is an integer number (10668941946).

Almost surely, 2^78238907538 is an apocalyptic number.

78238907538 is an abundant number, since it is smaller than the sum of its proper divisors (92464163598).

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

78238907538 is a wasteful number, since it uses less digits than its factorization.

78238907538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1185438009.

The product of its (nonzero) digits is 20321280, while the sum is 60.

The spelling of 78238907538 in words is "seventy-eight billion, two hundred thirty-eight million, nine hundred seven thousand, five hundred thirty-eight".