25305520 has 80 divisors (see below), whose sum is σ = 65085120. Its totient is φ = 9101312.

The previous prime is 25305509. The next prime is 25305529. The reversal of 25305520 is 2550352.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 25305491 and 25305500.

It is not an unprimeable number, because it can be changed into a prime (25305529) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30876 + ... + 31684.

It is an arithmetic number, because the mean of its divisors is an integer number (813564).

Almost surely, 2^25305520 is an apocalyptic number.

25305520 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 25305520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32542560).

25305520 is an abundant number, since it is smaller than the sum of its proper divisors (39779600).

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

25305520 is a wasteful number, since it uses less digits than its factorization.

25305520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 862 (or 856 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 22.

The square root of 25305520 is about 5030.4592235700. The cubic root of 25305520 is about 293.5880821857.

Adding to 25305520 its reverse (2550352), we get a palindrome (27855872).

The spelling of 25305520 in words is "twenty-five million, three hundred five thousand, five hundred twenty".