78391338 has 16 divisors (see below), whose sum is σ = 156926496. Its totient is φ = 26106480.

The previous prime is 78391309. The next prime is 78391349. The reversal of 78391338 is 83319387.

It is a super-2 number, since 2×78391338² = 12290403746860488, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78391338.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1893 + ... + 12663.

It is an arithmetic number, because the mean of its divisors is an integer number (9807906).

Almost surely, 2^78391338 is an apocalyptic number.

78391338 is an abundant number, since it is smaller than the sum of its proper divisors (78535158).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78391338 is a wasteful number, since it uses less digits than its factorization.

78391338 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11989.

The product of its digits is 108864, while the sum is 42.

The square root of 78391338 is about 8853.8882983693. Note that the first 3 decimals coincide. The cubic root of 78391338 is about 427.9792293469.

The spelling of 78391338 in words is "seventy-eight million, three hundred ninety-one thousand, three hundred thirty-eight".