25521325320 has 128 divisors (see below), whose sum is σ = 81400723200. Its totient is φ = 6386924544.

The previous prime is 25521325303. The next prime is 25521325321. The reversal of 25521325320 is 2352312552.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (25521325321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 59046 + ... + 233514.

It is an arithmetic number, because the mean of its divisors is an integer number (635943150).

Almost surely, 2^25521325320 is an apocalyptic number.

25521325320 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 25521325320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40700361600).

25521325320 is an abundant number, since it is smaller than the sum of its proper divisors (55879397880).

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

25521325320 is a wasteful number, since it uses less digits than its factorization.

25521325320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174559 (or 174555 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 30.

Adding to 25521325320 its reverse (2352312552), we get a palindrome (27873637872).

The spelling of 25521325320 in words is "twenty-five billion, five hundred twenty-one million, three hundred twenty-five thousand, three hundred twenty".