2505978 has 40 divisors (see below), whose sum is σ = 5808000. Its totient is φ = 806760.

The previous prime is 2505917. The next prime is 2505983. The reversal of 2505978 is 8795052.

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 4773 + ... + 5271.

It is an arithmetic number, because the mean of its divisors is an integer number (145200).

2^2505978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2505978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2904000).

2505978 is an abundant number, since it is smaller than the sum of its proper divisors (3302022).

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

2505978 is a wasteful number, since it uses less digits than its factorization.

2505978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544 (or 535 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 36.

The square root of 2505978 is about 1583.0281109317. The cubic root of 2505978 is about 135.8289733086.

The spelling of 2505978 in words is "two million, five hundred five thousand, nine hundred seventy-eight".