25817261 has 2 divisors, whose sum is σ = 25817262. Its totient is φ = 25817260.

The previous prime is 25817227. The next prime is 25817269. The reversal of 25817261 is 16271852.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25694761 + 122500 = 5069^2 + 350^2 .

It is a cyclic number.

It is not a de Polignac number, because 25817261 - 2²² = 21622957 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25817269) 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, 12908630 + 12908631.

It is an arithmetic number, because the mean of its divisors is an integer number (12908631).

Almost surely, 2^25817261 is an apocalyptic number.

It is an amenable number.

25817261 is a deficient number, since it is larger than the sum of its proper divisors (1).

25817261 is an equidigital number, since it uses as much as digits as its factorization.

25817261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6720, while the sum is 32.

The square root of 25817261 is about 5081.0688836110. The cubic root of 25817261 is about 295.5539185645.

The spelling of 25817261 in words is "twenty-five million, eight hundred seventeen thousand, two hundred sixty-one".