25749520 has 40 divisors (see below), whose sum is σ = 61007256. Its totient is φ = 10103808.

The previous prime is 25749469. The next prime is 25749527. The reversal of 25749520 is 2594752.

It can be written as a sum of positive squares in 4 ways, for example, as 10036224 + 15713296 = 3168^2 + 3964^2 .

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

It is not an unprimeable number, because it can be changed into a prime (25749527) 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, 1204 + ... + 7276.

Almost surely, 2^25749520 is an apocalyptic number.

25749520 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 25749520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30503628).

25749520 is an abundant number, since it is smaller than the sum of its proper divisors (35257736).

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

25749520 is a wasteful number, since it uses less digits than its factorization.

25749520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6139 (or 6133 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 34.

The square root of 25749520 is about 5074.3984865203. The cubic root of 25749520 is about 295.2951943145.

The spelling of 25749520 in words is "twenty-five million, seven hundred forty-nine thousand, five hundred twenty".