25666000 has 80 divisors (see below), whose sum is σ = 63777168. Its totient is φ = 9984000.

The previous prime is 25665973. The next prime is 25666001. The reversal of 25666000 is 66652.

It can be written as a sum of positive squares in 8 ways, for example, as 22963264 + 2702736 = 4792^2 + 1644^2 .

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 (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25666001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81844 + ... + 82156.

Almost surely, 2^25666000 is an apocalyptic number.

25666000 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 25666000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31888584).

25666000 is an abundant number, since it is smaller than the sum of its proper divisors (38111168).

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

25666000 is a wasteful number, since it uses less digits than its factorization.

25666000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 377 (or 361 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 25666000 is about 5066.1622555935. The cubic root of 25666000 is about 294.9755797079.

The spelling of 25666000 in words is "twenty-five million, six hundred sixty-six thousand".