25709661 has 12 divisors (see below), whose sum is σ = 39320892. Its totient is φ = 16131456.

The previous prime is 25709659. The next prime is 25709669. The reversal of 25709661 is 16690752.

It can be written as a sum of positive squares in 2 ways, for example, as 20304036 + 5405625 = 4506^2 + 2325^2 .

It is not a de Polignac number, because 25709661 - 2¹ = 25709659 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25709669) 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 11 ways as a sum of consecutive naturals, for example, 83866 + ... + 84171.

It is an arithmetic number, because the mean of its divisors is an integer number (3276741).

Almost surely, 2^25709661 is an apocalyptic number.

It is an amenable number.

25709661 is a deficient number, since it is larger than the sum of its proper divisors (13611231).

25709661 is a wasteful number, since it uses less digits than its factorization.

25709661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168060 (or 168057 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 36.

The square root of 25709661 is about 5070.4695048881. The cubic root of 25709661 is about 295.1427481123.

The spelling of 25709661 in words is "twenty-five million, seven hundred nine thousand, six hundred sixty-one".