25669980 has 96 divisors (see below), whose sum is σ = 91284480. Its totient is φ = 5866560.

The previous prime is 25669961. The next prime is 25669981. The reversal of 25669980 is 8996652.

25669980 is a `hidden beast` number, since 2 + 566 + 9 + 9 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25669981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 385 + ... + 7175.

It is an arithmetic number, because the mean of its divisors is an integer number (950880).

Almost surely, 2^25669980 is an apocalyptic number.

25669980 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 25669980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45642240).

25669980 is an abundant number, since it is smaller than the sum of its proper divisors (65614500).

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

25669980 is a wasteful number, since it uses less digits than its factorization.

25669980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6816 (or 6808 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The square root of 25669980 is about 5066.5550426301. Note that the first 3 decimals coincide. The cubic root of 25669980 is about 294.9908261056.

The spelling of 25669980 in words is "twenty-five million, six hundred sixty-nine thousand, nine hundred eighty".