78688438 has 8 divisors (see below), whose sum is σ = 118962432. Its totient is φ = 39034296.

The previous prime is 78688417. The next prime is 78688439. The reversal of 78688438 is 83488687.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78688439) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 154645 + ... + 155152.

It is an arithmetic number, because the mean of its divisors is an integer number (14870304).

Almost surely, 2^78688438 is an apocalyptic number.

78688438 is a deficient number, since it is larger than the sum of its proper divisors (40273994).

78688438 is a wasteful number, since it uses less digits than its factorization.

78688438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 309926.

The product of its digits is 2064384, while the sum is 52.

The square root of 78688438 is about 8870.6503707451. The cubic root of 78688438 is about 428.5192223921.

The spelling of 78688438 in words is "seventy-eight million, six hundred eighty-eight thousand, four hundred thirty-eight".