25449978 has 8 divisors (see below), whose sum is σ = 50899968. Its totient is φ = 8483324.

The previous prime is 25449959. The next prime is 25449989. The reversal of 25449978 is 87994452.

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

25449978 is an admirable number.

It is a Curzon number.

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 3 ways as a sum of consecutive naturals, for example, 2120826 + ... + 2120837.

It is an arithmetic number, because the mean of its divisors is an integer number (6362496).

Almost surely, 2^25449978 is an apocalyptic number.

25449978 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.

25449978 is a wasteful number, since it uses less digits than its factorization.

25449978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4241668.

The product of its digits is 725760, while the sum is 48.

The square root of 25449978 is about 5044.7971217880. The cubic root of 25449978 is about 294.1456772611.

The spelling of 25449978 in words is "twenty-five million, four hundred forty-nine thousand, nine hundred seventy-eight".