25641709 has 2 divisors, whose sum is σ = 25641710. Its totient is φ = 25641708.

The previous prime is 25641691. The next prime is 25641731. The reversal of 25641709 is 90714652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25532809 + 108900 = 5053^2 + 330^2 .

It is a cyclic number.

It is not a de Polignac number, because 25641709 - 2¹⁷ = 25510637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25641739) 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 as a sum of consecutive naturals, namely, 12820854 + 12820855.

It is an arithmetic number, because the mean of its divisors is an integer number (12820855).

Almost surely, 2^25641709 is an apocalyptic number.

It is an amenable number.

25641709 is a deficient number, since it is larger than the sum of its proper divisors (1).

25641709 is an equidigital number, since it uses as much as digits as its factorization.

25641709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 25641709 is about 5063.7643112609. The cubic root of 25641709 is about 294.8824926997.

The spelling of 25641709 in words is "twenty-five million, six hundred forty-one thousand, seven hundred nine".