78336418 has 4 divisors (see below), whose sum is σ = 117504630. Its totient is φ = 39168208.

The previous prime is 78336409. The next prime is 78336421. The reversal of 78336418 is 81463387.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81463387 = 8647 ⋅9421.

It can be written as a sum of positive squares in only one way, i.e., 74080449 + 4255969 = 8607^2 + 2063^2 .

It is a super-2 number, since 2×78336418² = 12273188770141448, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19584103 + ... + 19584106.

Almost surely, 2^78336418 is an apocalyptic number.

78336418 is a deficient number, since it is larger than the sum of its proper divisors (39168212).

78336418 is a wasteful number, since it uses less digits than its factorization.

78336418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39168211.

The product of its digits is 96768, while the sum is 40.

The square root of 78336418 is about 8850.7862927539. The cubic root of 78336418 is about 427.8792603494.

The spelling of 78336418 in words is "seventy-eight million, three hundred thirty-six thousand, four hundred eighteen".