25640544 has 48 divisors (see below), whose sum is σ = 68085360. Its totient is φ = 8448000.

The previous prime is 25640543. The next prime is 25640579. The reversal of 25640544 is 44504652.

It is a tau number, because it is divible by the number of its divisors (48).

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25640543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7044 + ... + 10044.

It is an arithmetic number, because the mean of its divisors is an integer number (1418445).

Almost surely, 2^25640544 is an apocalyptic number.

25640544 is a gapful number since it is divisible by the number (24) 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 25640544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34042680).

25640544 is an abundant number, since it is smaller than the sum of its proper divisors (42444816).

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

25640544 is a wasteful number, since it uses less digits than its factorization.

25640544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3103 (or 3095 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 30.

The square root of 25640544 is about 5063.6492769543. The cubic root of 25640544 is about 294.8780267557.

The spelling of 25640544 in words is "twenty-five million, six hundred forty thousand, five hundred forty-four".