78854399 has 16 divisors (see below), whose sum is σ = 86873472. Its totient is φ = 71135328.

The previous prime is 78854371. The next prime is 78854401. The reversal of 78854399 is 99345887.

It is a Cunningham number, because it is equal to 8880²-1.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78854399 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78854399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78854309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115112 + ... + 115794.

It is an arithmetic number, because the mean of its divisors is an integer number (5429592).

Almost surely, 2^78854399 is an apocalyptic number.

78854399 is a deficient number, since it is larger than the sum of its proper divisors (8019073).

78854399 is a wasteful number, since it uses less digits than its factorization.

78854399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 886.

The product of its digits is 2177280, while the sum is 53.

The square root of 78854399 is about 8879.9999436937. Note that the first 4 decimals coincide. The cubic root of 78854399 is about 428.8202727169.

The spelling of 78854399 in words is "seventy-eight million, eight hundred fifty-four thousand, three hundred ninety-nine".