7889978 has 16 divisors (see below), whose sum is σ = 12513120. Its totient is φ = 3720816.

The previous prime is 7889977. The next prime is 7890013. The reversal of 7889978 is 8799887.

It is not an unprimeable number, because it can be changed into a prime (7889977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14825 + ... + 15347.

It is an arithmetic number, because the mean of its divisors is an integer number (782070).

Almost surely, 2^7889978 is an apocalyptic number.

7889978 is a deficient number, since it is larger than the sum of its proper divisors (4623142).

7889978 is a wasteful number, since it uses less digits than its factorization.

7889978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 941.

The product of its digits is 2032128, while the sum is 56.

The square root of 7889978 is about 2808.9104649312. The cubic root of 7889978 is about 199.0789145198.

Subtracting 7889978 from its reverse (8799887), we obtain a palindrome (909909).

The spelling of 7889978 in words is "seven million, eight hundred eighty-nine thousand, nine hundred seventy-eight".