25644816 has 160 divisors (see below), whose sum is σ = 80352000. Its totient is φ = 7805952.

The previous prime is 25644799. The next prime is 25644821. The reversal of 25644816 is 61844652.

25644816 is a `hidden beast` number, since 2 + 5 + 644 + 8 + 1 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 288100 + ... + 288188.

It is an arithmetic number, because the mean of its divisors is an integer number (502200).

Almost surely, 2^25644816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25644816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40176000).

25644816 is an abundant number, since it is smaller than the sum of its proper divisors (54707184).

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

25644816 is a wasteful number, since it uses less digits than its factorization.

25644816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158 (or 146 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 25644816 is about 5064.0710895484. The cubic root of 25644816 is about 294.8944025000.

The spelling of 25644816 in words is "twenty-five million, six hundred forty-four thousand, eight hundred sixteen".