25503440 has 20 divisors (see below), whose sum is σ = 59295684. Its totient is φ = 10201344.

The previous prime is 25503437. The next prime is 25503449. The reversal of 25503440 is 4430552.

It can be written as a sum of positive squares in 2 ways, for example, as 7997584 + 17505856 = 2828^2 + 4184^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-3 number, since 3×25503440³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25503449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 159317 + ... + 159476.

Almost surely, 2^25503440 is an apocalyptic number.

25503440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25503440 is an abundant number, since it is smaller than the sum of its proper divisors (33792244).

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

25503440 is a wasteful number, since it uses less digits than its factorization.

25503440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318806 (or 318800 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 23.

The square root of 25503440 is about 5050.0930684493. The cubic root of 25503440 is about 294.3515008521.

Adding to 25503440 its reverse (4430552), we get a palindrome (29933992).

The spelling of 25503440 in words is "twenty-five million, five hundred three thousand, four hundred forty".