25665420 has 96 divisors (see below), whose sum is σ = 80591616. Its totient is φ = 6048000.

The previous prime is 25665403. The next prime is 25665421. The reversal of 25665420 is 2456652.

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

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (25665421) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23895 + ... + 24945.

It is an arithmetic number, because the mean of its divisors is an integer number (839496).

Almost surely, 2^25665420 is an apocalyptic number.

25665420 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 25665420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40295808).

25665420 is an abundant number, since it is smaller than the sum of its proper divisors (54926196).

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

25665420 is a wasteful number, since it uses less digits than its factorization.

25665420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1111 (or 1109 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

The square root of 25665420 is about 5066.1050127292. The cubic root of 25665420 is about 294.9733577395.

The spelling of 25665420 in words is "twenty-five million, six hundred sixty-five thousand, four hundred twenty".