25805947 has 2 divisors, whose sum is σ = 25805948. Its totient is φ = 25805946.

The previous prime is 25805869. The next prime is 25805957. The reversal of 25805947 is 74950852.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25805947 is a prime.

It is not a weakly prime, because it can be changed into another prime (25805957) 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, 12902973 + 12902974.

It is an arithmetic number, because the mean of its divisors is an integer number (12902974).

Almost surely, 2^25805947 is an apocalyptic number.

25805947 is a deficient number, since it is larger than the sum of its proper divisors (1).

25805947 is an equidigital number, since it uses as much as digits as its factorization.

25805947 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 100800, while the sum is 40.

The square root of 25805947 is about 5079.9554131902. The cubic root of 25805947 is about 295.5107383368.

The spelling of 25805947 in words is "twenty-five million, eight hundred five thousand, nine hundred forty-seven".