78506634731165 has 4 divisors (see below), whose sum is σ = 94207961677404. Its totient is φ = 62805307784928.

The previous prime is 78506634731143. The next prime is 78506634731167. The reversal of 78506634731165 is 56113743660587.

It is a happy number.

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 36327597908644 + 42179036822521 = 6027238^2 + 6494539^2 .

It is a cyclic number.

It is not a de Polignac number, because 78506634731165 - 2¹⁰ = 78506634730141 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78506634731098 and 78506634731107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78506634731167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7850663473112 + ... + 7850663473121.

It is an arithmetic number, because the mean of its divisors is an integer number (23551990419351).

Almost surely, 2^{78506634731165} is an apocalyptic number.

It is an amenable number.

78506634731165 is a deficient number, since it is larger than the sum of its proper divisors (15701326946239).

78506634731165 is a wasteful number, since it uses less digits than its factorization.

78506634731165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15701326946238.

The product of its (nonzero) digits is 76204800, while the sum is 62.

The spelling of 78506634731165 in words is "seventy-eight trillion, five hundred six billion, six hundred thirty-four million, seven hundred thirty-one thousand, one hundred sixty-five".