25661705 has 4 divisors (see below), whose sum is σ = 30794052. Its totient is φ = 20529360.

The previous prime is 25661677. The next prime is 25661717. The reversal of 25661705 is 50716652.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20106256 + 5555449 = 4484^2 + 2357^2 .

It is not a de Polignac number, because 25661705 - 2²⁰ = 24613129 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2566166 + ... + 2566175.

It is an arithmetic number, because the mean of its divisors is an integer number (7698513).

Almost surely, 2^25661705 is an apocalyptic number.

It is an amenable number.

25661705 is a deficient number, since it is larger than the sum of its proper divisors (5132347).

25661705 is an equidigital number, since it uses as much as digits as its factorization.

25661705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5132346.

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 25661705 is about 5065.7383469737. The cubic root of 25661705 is about 294.9591248547.

The spelling of 25661705 in words is "twenty-five million, six hundred sixty-one thousand, seven hundred five".