25566816 has 144 divisors (see below), whose sum is σ = 77220864. Its totient is φ = 7392000.

The previous prime is 25566797. The next prime is 25566833. The reversal of 25566816 is 61866552.

It is a zygodrome in base 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 360061 + ... + 360131.

It is an arithmetic number, because the mean of its divisors is an integer number (536256).

Almost surely, 2^25566816 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 25566816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38610432).

25566816 is an abundant number, since it is smaller than the sum of its proper divisors (51654048).

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

25566816 is a wasteful number, since it uses less digits than its factorization.

25566816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 118 counting only the distinct ones).

The product of its digits is 86400, while the sum is 39.

The square root of 25566816 is about 5056.3639109542. The cubic root of 25566816 is about 294.5951201393.

The spelling of 25566816 in words is "twenty-five million, five hundred sixty-six thousand, eight hundred sixteen".