25515240 has 32 divisors (see below), whose sum is σ = 76546080. Its totient is φ = 6804032.

The previous prime is 25515239. The next prime is 25515241. The reversal of 25515240 is 4251552.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (25515239) and next prime (25515241).

It is a super-3 number, since 3×25515240³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 25515240.

It is not an unprimeable number, because it can be changed into a prime (25515241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 106194 + ... + 106433.

It is an arithmetic number, because the mean of its divisors is an integer number (2392065).

Almost surely, 2^25515240 is an apocalyptic number.

25515240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25515240 is an abundant number, since it is smaller than the sum of its proper divisors (51030840).

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

25515240 is a wasteful number, since it uses less digits than its factorization.

25515240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212641 (or 212637 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 25515240 is about 5051.2612286438. The cubic root of 25515240 is about 294.3968909663.

Adding to 25515240 its reverse (4251552), we get a palindrome (29766792).

The spelling of 25515240 in words is "twenty-five million, five hundred fifteen thousand, two hundred forty".