25563816 has 64 divisors (see below), whose sum is σ = 74760000. Its totient is φ = 8071488.

The previous prime is 25563803. The next prime is 25563821. The reversal of 25563816 is 61836552.

25563816 is a `hidden beast` number, since 2 + 5 + 5 + 638 + 16 = 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 polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 990 + ... + 7218.

It is an arithmetic number, because the mean of its divisors is an integer number (1168125).

Almost surely, 2^25563816 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 25563816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37380000).

25563816 is an abundant number, since it is smaller than the sum of its proper divisors (49196184).

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

25563816 is a wasteful number, since it uses less digits than its factorization.

25563816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6263 (or 6253 counting only the distinct ones).

The product of its digits is 43200, while the sum is 36.

The square root of 25563816 is about 5056.0672463882. The cubic root of 25563816 is about 294.5835971305.

The spelling of 25563816 in words is "twenty-five million, five hundred sixty-three thousand, eight hundred sixteen".