78368409 has 12 divisors (see below), whose sum is σ = 129370176. Its totient is φ = 44781912.

The previous prime is 78368401. The next prime is 78368413. The reversal of 78368409 is 90486387.

It is a happy number.

It is not a de Polignac number, because 78368409 - 2³ = 78368401 is a prime.

It is a super-2 number, since 2×78368409² = 12283215058382562, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78368401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 621909 + ... + 622034.

It is an arithmetic number, because the mean of its divisors is an integer number (10780848).

Almost surely, 2^78368409 is an apocalyptic number.

It is an amenable number.

78368409 is a deficient number, since it is larger than the sum of its proper divisors (51001767).

78368409 is a wasteful number, since it uses less digits than its factorization.

78368409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1243956 (or 1243953 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The square root of 78368409 is about 8852.5933488442. The cubic root of 78368409 is about 427.9374981518.

The spelling of 78368409 in words is "seventy-eight million, three hundred sixty-eight thousand, four hundred nine".