7878891 has 8 divisors (see below), whose sum is σ = 10789264. Its totient is φ = 5110560.

The previous prime is 7878887. The next prime is 7878911. The reversal of 7878891 is 1988787.

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

It is not a de Polignac number, because 7878891 - 2² = 7878887 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 7878891.

It is not an unprimeable number, because it can be changed into a prime (7878841) 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, 35380 + ... + 35601.

It is an arithmetic number, because the mean of its divisors is an integer number (1348658).

Almost surely, 2^7878891 is an apocalyptic number.

7878891 is a deficient number, since it is larger than the sum of its proper divisors (2910373).

7878891 is a wasteful number, since it uses less digits than its factorization.

7878891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71021.

The product of its digits is 225792, while the sum is 48.

The square root of 7878891 is about 2806.9362301271. The cubic root of 7878891 is about 198.9856222199.

The spelling of 7878891 in words is "seven million, eight hundred seventy-eight thousand, eight hundred ninety-one".