25561000 has 32 divisors (see below), whose sum is σ = 59815080. Its totient is φ = 10224000.

The previous prime is 25560989. The next prime is 25561007. The reversal of 25561000 is 16552.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 11737476 + 13823524 = 3426^2 + 3718^2 .

It is not an unprimeable number, because it can be changed into a prime (25561007) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11781 + ... + 13780.

Almost surely, 2^25561000 is an apocalyptic number.

25561000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25561000 is an abundant number, since it is smaller than the sum of its proper divisors (34254080).

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

25561000 is a wasteful number, since it uses less digits than its factorization.

25561000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25582 (or 25568 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 25561000 is about 5055.7887614100. The cubic root of 25561000 is about 294.5727800461.

Adding to 25561000 its reverse (16552), we get a palindrome (25577552).

The spelling of 25561000 in words is "twenty-five million, five hundred sixty-one thousand".