78506675004865 has 4 divisors (see below), whose sum is σ = 94208010005844. Its totient is φ = 62805340003888.

The previous prime is 78506675004859. The next prime is 78506675004869. The reversal of 78506675004865 is 56840057660587.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 53880238979856 + 24626436025009 = 7340316^2 + 4962503^2 .

It is a cyclic number.

It is not a de Polignac number, because 78506675004865 - 2⁴¹ = 76307651749313 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78506675004865.

It is not an unprimeable number, because it can be changed into a prime (78506675004869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7850667500482 + ... + 7850667500491.

It is an arithmetic number, because the mean of its divisors is an integer number (23552002501461).

Almost surely, 2^{78506675004865} is an apocalyptic number.

It is an amenable number.

78506675004865 is a deficient number, since it is larger than the sum of its proper divisors (15701335000979).

78506675004865 is a wasteful number, since it uses less digits than its factorization.

78506675004865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15701335000978.

The product of its (nonzero) digits is 338688000, while the sum is 67.

The spelling of 78506675004865 in words is "seventy-eight trillion, five hundred six billion, six hundred seventy-five million, four thousand, eight hundred sixty-five".