25816560 has 240 divisors, whose sum is σ = 101326848. Its totient is φ = 5322240.

The previous prime is 25816547. The next prime is 25816579. The reversal of 25816560 is 6561852.

It is a Cunningham number, because it is equal to 5081²-1.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 203217 + ... + 203343.

Almost surely, 2^25816560 is an apocalyptic number.

25816560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25816560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50663424).

25816560 is an abundant number, since it is smaller than the sum of its proper divisors (75510288).

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

25816560 is a wasteful number, since it uses less digits than its factorization.

25816560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 33.

The square root of 25816560 is about 5080.9999015942. Note that the first 4 decimals coincide. The cubic root of 25816560 is about 295.5512435432.

The spelling of 25816560 in words is "twenty-five million, eight hundred sixteen thousand, five hundred sixty".