2556818778 has 8 divisors (see below), whose sum is σ = 5113637568. Its totient is φ = 852272924.

The previous prime is 2556818767. The next prime is 2556818783. The reversal of 2556818778 is 8778186552.

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

2556818778 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 213068226 + ... + 213068237.

It is an arithmetic number, because the mean of its divisors is an integer number (639204696).

Almost surely, 2^2556818778 is an apocalyptic number.

2556818778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

2556818778 is a wasteful number, since it uses less digits than its factorization.

2556818778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426136468.

The product of its digits is 7526400, while the sum is 57.

The square root of 2556818778 is about 50564.9955799464. The cubic root of 2556818778 is about 1367.4138752636.

The spelling of 2556818778 in words is "two billion, five hundred fifty-six million, eight hundred eighteen thousand, seven hundred seventy-eight".