25581984 has 24 divisors (see below), whose sum is σ = 67152960. Its totient is φ = 8527296.

The previous prime is 25581979. The next prime is 25581989. The reversal of 25581984 is 48918552.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (25581979) and next prime (25581989).

It is a tau number, because it is divible by the number of its divisors (24).

It is not an unprimeable number, because it can be changed into a prime (25581989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133144 + ... + 133335.

It is an arithmetic number, because the mean of its divisors is an integer number (2798040).

Almost surely, 2^25581984 is an apocalyptic number.

25581984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

25581984 is an abundant number, since it is smaller than the sum of its proper divisors (41570976).

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

25581984 is a wasteful number, since it uses less digits than its factorization.

25581984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266492 (or 266484 counting only the distinct ones).

The product of its digits is 115200, while the sum is 42.

The square root of 25581984 is about 5057.8635806040. The cubic root of 25581984 is about 294.6533666754.

It can be divided in two parts, 25581 and 984, that added together give a triangular number (26565 = T₂₃₀).

The spelling of 25581984 in words is "twenty-five million, five hundred eighty-one thousand, nine hundred eighty-four".