25040640 has 72 divisors (see below), whose sum is σ = 79985808. Its totient is φ = 6676480.

The previous prime is 25040621. The next prime is 25040681. The reversal of 25040640 is 4604052.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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, 580 + ... + 7100.

It is an arithmetic number, because the mean of its divisors is an integer number (1110914).

Almost surely, 2^25040640 is an apocalyptic number.

25040640 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 25040640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39992904).

25040640 is an abundant number, since it is smaller than the sum of its proper divisors (54945168).

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

25040640 is an equidigital number, since it uses as much as digits as its factorization.

25040640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6545 (or 6531 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 25040640 is about 5004.0623497315. The cubic root of 25040640 is about 292.5601308184.

Adding to 25040640 its reverse (4604052), we get a palindrome (29644692).

The spelling of 25040640 in words is "twenty-five million, forty thousand, six hundred forty".