78438806 has 4 divisors (see below), whose sum is σ = 117658212. Its totient is φ = 39219402.

The previous prime is 78438803. The next prime is 78438839. The reversal of 78438806 is 60883487.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60883487 = 7 ⋅8697641.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78438803) 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 as a sum of consecutive naturals, namely, 19609700 + ... + 19609703.

It is an arithmetic number, because the mean of its divisors is an integer number (29414553).

Almost surely, 2^78438806 is an apocalyptic number.

78438806 is a deficient number, since it is larger than the sum of its proper divisors (39219406).

78438806 is a wasteful number, since it uses less digits than its factorization.

78438806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39219405.

The product of its (nonzero) digits is 258048, while the sum is 44.

The square root of 78438806 is about 8856.5685228535. The cubic root of 78438806 is about 428.0655961126.

The spelling of 78438806 in words is "seventy-eight million, four hundred thirty-eight thousand, eight hundred six".