25605840 has 160 divisors (see below), whose sum is σ = 88744320. Its totient is φ = 6064128.

The previous prime is 25605821. The next prime is 25605851. The reversal of 25605840 is 4850652.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 25605798 and 25605807.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 90339 + ... + 90621.

It is an arithmetic number, because the mean of its divisors is an integer number (554652).

Almost surely, 2^25605840 is an apocalyptic number.

25605840 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 25605840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44372160).

25605840 is an abundant number, since it is smaller than the sum of its proper divisors (63138480).

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

25605840 is a wasteful number, since it uses less digits than its factorization.

25605840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341 (or 335 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

The square root of 25605840 is about 5060.2213390325. The cubic root of 25605840 is about 294.7449293789.

The spelling of 25605840 in words is "twenty-five million, six hundred five thousand, eight hundred forty".