25443840 has 80 divisors (see below), whose sum is σ = 81365328. Its totient is φ = 6782976.

The previous prime is 25443797. The next prime is 25443863. The reversal of 25443840 is 4834452.

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

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 = 25443798 and 25443807.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6024 + ... + 9336.

Almost surely, 2^25443840 is an apocalyptic number.

25443840 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 25443840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40682664).

25443840 is an abundant number, since it is smaller than the sum of its proper divisors (55921488).

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

25443840 is an equidigital number, since it uses as much as digits as its factorization.

25443840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3339 (or 3323 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 30.

The square root of 25443840 is about 5044.1887355649. The cubic root of 25443840 is about 294.1220281073.

The spelling of 25443840 in words is "twenty-five million, four hundred forty-three thousand, eight hundred forty".