2778888 has 96 divisors (see below), whose sum is σ = 8618400. Its totient is φ = 741888.

The previous prime is 2778877. The next prime is 2778901. The reversal of 2778888 is 8888772.

It is a Cunningham number, because it is equal to 1667²-1.

It is a nude number because it is divisible by every one of its digits.

It is a plaindrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19923 + ... + 20061.

It is an arithmetic number, because the mean of its divisors is an integer number (89775).

2^2778888 is an apocalyptic number.

2778888 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2778888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4309200).

2778888 is an abundant number, since it is smaller than the sum of its proper divisors (5839512).

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

2778888 is a wasteful number, since it uses less digits than its factorization.

2778888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179 (or 168 counting only the distinct ones).

The product of its digits is 401408, while the sum is 48.

The square root of 2778888 is about 1666.9997000600. Note that the first 3 decimals coincide. The cubic root of 2778888 is about 140.5908363429.

The spelling of 2778888 in words is "two million, seven hundred seventy-eight thousand, eight hundred eighty-eight".