25536 has 56 divisors (see below), whose sum is σ = 81280. Its totient is φ = 6912.

The previous prime is 25523. The next prime is 25537. The reversal of 25536 is 63552.

25536 is an esthetic number in base 15, because in such base its adjacent digits differ by 1.

It is a tau number, because it is divible by the number of its divisors (56).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a nialpdrome in base 14.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25537) by changing a digit.

25536 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1335 + ... + 1353.

2²⁵⁵³⁶ 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 25536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40640).

25536 is an abundant number, since it is smaller than the sum of its proper divisors (55744).

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

25536 is a wasteful number, since it uses less digits than its factorization.

25536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41 (or 31 counting only the distinct ones).

The product of its digits is 900, while the sum is 21.

The square root of 25536 is about 159.7998748435. The cubic root of 25536 is about 29.4476712838.

It can be divided in two parts, 255 and 36, that multiplied together give a triangular number (9180 = T₁₃₅).

The spelling of 25536 in words is "twenty-five thousand, five hundred thirty-six".