2784978 has 72 divisors (see below), whose sum is σ = 7435584. Its totient is φ = 736560.

The previous prime is 2784973. The next prime is 2784979. The reversal of 2784978 is 8794872.

It is a super-2 number, since 2×2784978² = 15512204920968, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2784973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 89823 + ... + 89853.

It is an arithmetic number, because the mean of its divisors is an integer number (103272).

2^2784978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2784978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3717792).

2784978 is an abundant number, since it is smaller than the sum of its proper divisors (4650606).

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

2784978 is a wasteful number, since it uses less digits than its factorization.

2784978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100 (or 66 counting only the distinct ones).

The product of its digits is 225792, while the sum is 45.

The square root of 2784978 is about 1668.8253353782. The cubic root of 2784978 is about 140.6934641439.

The spelling of 2784978 in words is "two million, seven hundred eighty-four thousand, nine hundred seventy-eight".