2687778 has 48 divisors (see below), whose sum is σ = 6364800. Its totient is φ = 816480.

The previous prime is 2687777. The next prime is 2687779. The reversal of 2687778 is 8777862.

It is an interprime number because it is at equal distance from previous prime (2687777) and next prime (2687779).

It is not an unprimeable number, because it can be changed into a prime (2687771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9783 + ... + 10053.

It is an arithmetic number, because the mean of its divisors is an integer number (132600).

2^2687778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2687778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3182400).

2687778 is an abundant number, since it is smaller than the sum of its proper divisors (3677022).

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

2687778 is a wasteful number, since it uses less digits than its factorization.

2687778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 327 (or 324 counting only the distinct ones).

The product of its digits is 263424, while the sum is 45.

The square root of 2687778 is about 1639.4444180880. Note that the first 4 decimals coincide. The cubic root of 2687778 is about 139.0372379226.

The spelling of 2687778 in words is "two million, six hundred eighty-seven thousand, seven hundred seventy-eight".