25440520 has 64 divisors (see below), whose sum is σ = 66971520. Its totient is φ = 8515584.

The previous prime is 25440479. The next prime is 25440521. The reversal of 25440520 is 2504452.

It is a junction number, because it is equal to n+sod(n) for n = 25440491 and 25440500.

It is not an unprimeable number, because it can be changed into a prime (25440521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10984 + ... + 13096.

It is an arithmetic number, because the mean of its divisors is an integer number (1046430).

Almost surely, 2^25440520 is an apocalyptic number.

25440520 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 25440520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33485760).

25440520 is an abundant number, since it is smaller than the sum of its proper divisors (41531000).

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

25440520 is a wasteful number, since it uses less digits than its factorization.

25440520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2174 (or 2170 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 22.

The square root of 25440520 is about 5043.8596332571. The cubic root of 25440520 is about 294.1092348653.

Adding to 25440520 its reverse (2504452), we get a palindrome (27944972).

The spelling of 25440520 in words is "twenty-five million, four hundred forty thousand, five hundred twenty".