25689040 has 80 divisors (see below), whose sum is σ = 68151888. Its totient is φ = 8921088.

The previous prime is 25689031. The next prime is 25689043. The reversal of 25689040 is 4098652.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 968256 + 24720784 = 984^2 + 4972^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×25689040² = 1319853552243200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a junction number, because it is equal to n+sod(n) for n = 25688987 and 25689005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25689043) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16954 + ... + 18406.

Almost surely, 2^25689040 is an apocalyptic number.

25689040 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 25689040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34075944).

25689040 is an abundant number, since it is smaller than the sum of its proper divisors (42462848).

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

25689040 is a wasteful number, since it uses less digits than its factorization.

25689040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1496 (or 1490 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 25689040 is about 5068.4356560975. The cubic root of 25689040 is about 295.0638184250.

The spelling of 25689040 in words is "twenty-five million, six hundred eighty-nine thousand, forty".