7878999 has 8 divisors (see below), whose sum is σ = 10662400. Its totient is φ = 5174136.

The previous prime is 7878989. The next prime is 7879021. The reversal of 7878999 is 9998787.

It is a happy number.

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

It is not a de Polignac number, because 7878999 - 2⁵ = 7878967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7878979) 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 in 7 ways as a sum of consecutive naturals, for example, 19399 + ... + 19800.

It is an arithmetic number, because the mean of its divisors is an integer number (1332800).

Almost surely, 2^7878999 is an apocalyptic number.

7878999 is a deficient number, since it is larger than the sum of its proper divisors (2783401).

7878999 is a wasteful number, since it uses less digits than its factorization.

7878999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39269.

The product of its digits is 2286144, while the sum is 57.

The square root of 7878999 is about 2806.9554681184. The cubic root of 7878999 is about 198.9865314151.

The spelling of 7878999 in words is "seven million, eight hundred seventy-eight thousand, nine hundred ninety-nine".