7878978 has 32 divisors (see below), whose sum is σ = 17812800. Its totient is φ = 2580768.

The previous prime is 7878967. The next prime is 7878979. The reversal of 7878978 is 8798787.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an Ulam number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (7878979) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1950 + ... + 4422.

It is an arithmetic number, because the mean of its divisors is an integer number (556650).

Almost surely, 2^7878978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7878978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8906400).

7878978 is an abundant number, since it is smaller than the sum of its proper divisors (9933822).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7878978 is a wasteful number, since it uses less digits than its factorization.

7878978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2543 (or 2537 counting only the distinct ones).

The product of its digits is 1580544, while the sum is 54.

The square root of 7878978 is about 2806.9517274082. The cubic root of 7878978 is about 198.9863546278.

The spelling of 7878978 in words is "seven million, eight hundred seventy-eight thousand, nine hundred seventy-eight".