25520240 has 40 divisors (see below), whose sum is σ = 60183648. Its totient is φ = 10062080.

The previous prime is 25520221. The next prime is 25520267. The reversal of 25520240 is 4202552.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3434 + ... + 7926.

Almost surely, 2^25520240 is an apocalyptic number.

25520240 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 25520240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30091824).

25520240 is an abundant number, since it is smaller than the sum of its proper divisors (34663408).

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

25520240 is a wasteful number, since it uses less digits than its factorization.

25520240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4577 (or 4571 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 20.

The square root of 25520240 is about 5051.7561302977. The cubic root of 25520240 is about 294.4161198443.

Adding to 25520240 its reverse (4202552), we get a palindrome (29722792).

The spelling of 25520240 in words is "twenty-five million, five hundred twenty thousand, two hundred forty".