78923165 has 4 divisors (see below), whose sum is σ = 94707804. Its totient is φ = 63138528.

The previous prime is 78923161. The next prime is 78923167. The reversal of 78923165 is 56132987.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56132987 = 181 ⋅310127.

It can be written as a sum of positive squares in 2 ways, for example, as 45306361 + 33616804 = 6731^2 + 5798^2 .

It is a cyclic number.

It is not a de Polignac number, because 78923165 - 2² = 78923161 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78923161) 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 3 ways as a sum of consecutive naturals, for example, 7892312 + ... + 7892321.

It is an arithmetic number, because the mean of its divisors is an integer number (23676951).

Almost surely, 2^78923165 is an apocalyptic number.

It is an amenable number.

78923165 is a deficient number, since it is larger than the sum of its proper divisors (15784639).

78923165 is a wasteful number, since it uses less digits than its factorization.

78923165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15784638.

The product of its digits is 90720, while the sum is 41.

The square root of 78923165 is about 8883.8710593975. The cubic root of 78923165 is about 428.9448892571.

The spelling of 78923165 in words is "seventy-eight million, nine hundred twenty-three thousand, one hundred sixty-five".