25440400 has 30 divisors (see below), whose sum is σ = 61121522. Its totient is φ = 10176000.

The previous prime is 25440397. The next prime is 25440403. The reversal of 25440400 is 404452.

It is an interprime number because it is at equal distance from previous prime (25440397) and next prime (25440403).

It can be written as a sum of positive squares in 3 ways, for example, as 5513104 + 19927296 = 2348^2 + 4464^2 .

It is not an unprimeable number, because it can be changed into a prime (25440403) 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 5 ways as a sum of consecutive naturals, for example, 31401 + ... + 32200.

Almost surely, 2^25440400 is an apocalyptic number.

25440400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25440400 is an abundant number, since it is smaller than the sum of its proper divisors (35681122).

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

25440400 is a wasteful number, since it uses less digits than its factorization.

25440400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63619 (or 63608 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 19.

The square root of 25440400 is about 5043.8477375908. The cubic root of 25440400 is about 294.1087724381.

Adding to 25440400 its reverse (404452), we get a palindrome (25844852).

The spelling of 25440400 in words is "twenty-five million, four hundred forty thousand, four hundred".