78439105 has 8 divisors (see below), whose sum is σ = 99663912. Its totient is φ = 59059968.

The previous prime is 78439103. The next prime is 78439117. The reversal of 78439105 is 50193487.

It can be written as a sum of positive squares in 4 ways, for example, as 22353984 + 56085121 = 4728^2 + 7489^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78439105 - 2¹ = 78439103 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78439103) 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, 461322 + ... + 461491.

It is an arithmetic number, because the mean of its divisors is an integer number (12457989).

Almost surely, 2^78439105 is an apocalyptic number.

It is an amenable number.

78439105 is a deficient number, since it is larger than the sum of its proper divisors (21224807).

78439105 is a wasteful number, since it uses less digits than its factorization.

78439105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 922835.

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 78439105 is about 8856.5854029643. The cubic root of 78439105 is about 428.0661400247.

The spelling of 78439105 in words is "seventy-eight million, four hundred thirty-nine thousand, one hundred five".