78438146 has 4 divisors (see below), whose sum is σ = 117657222. Its totient is φ = 39219072.

The previous prime is 78438097. The next prime is 78438167. The reversal of 78438146 is 64183487.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 64183487 = 5003 ⋅12829.

It can be written as a sum of positive squares in only one way, i.e., 49547521 + 28890625 = 7039^2 + 5375^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 19609535 + ... + 19609538.

Almost surely, 2^78438146 is an apocalyptic number.

78438146 is a deficient number, since it is larger than the sum of its proper divisors (39219076).

78438146 is a wasteful number, since it uses less digits than its factorization.

78438146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39219075.

The product of its digits is 129024, while the sum is 41.

The square root of 78438146 is about 8856.5312622945. The cubic root of 78438146 is about 428.0643954990.

The spelling of 78438146 in words is "seventy-eight million, four hundred thirty-eight thousand, one hundred forty-six".