25805543 has 2 divisors, whose sum is σ = 25805544. Its totient is φ = 25805542.

The previous prime is 25805537. The next prime is 25805567. The reversal of 25805543 is 34550852.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25805543 - 2¹⁶ = 25740007 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25805503) 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, 12902771 + 12902772.

It is an arithmetic number, because the mean of its divisors is an integer number (12902772).

Almost surely, 2^25805543 is an apocalyptic number.

25805543 is a deficient number, since it is larger than the sum of its proper divisors (1).

25805543 is an equidigital number, since it uses as much as digits as its factorization.

25805543 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24000, while the sum is 32.

The square root of 25805543 is about 5079.9156489060. The cubic root of 25805543 is about 295.5091962251.

The spelling of 25805543 in words is "twenty-five million, eight hundred five thousand, five hundred forty-three".