2978778 has 32 divisors (see below), whose sum is σ = 6570432. Its totient is φ = 900240.

The previous prime is 2978771. The next prime is 2978783. The reversal of 2978778 is 8778792.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (2978771) 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, 7800 + ... + 8172.

It is an arithmetic number, because the mean of its divisors is an integer number (205326).

2^2978778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2978778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3285216).

2978778 is an abundant number, since it is smaller than the sum of its proper divisors (3591654).

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

2978778 is a wasteful number, since it uses less digits than its factorization.

2978778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411 (or 389 counting only the distinct ones).

The product of its digits is 395136, while the sum is 48.

The square root of 2978778 is about 1725.9136710740. The cubic root of 2978778 is about 143.8840695012.

The spelling of 2978778 in words is "two million, nine hundred seventy-eight thousand, seven hundred seventy-eight".