25564681 has 2 divisors, whose sum is σ = 25564682. Its totient is φ = 25564680.

The previous prime is 25564667. The next prime is 25564697. The reversal of 25564681 is 18646552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24950025 + 614656 = 4995^2 + 784^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25564681 is a prime.

It is a super-2 number, since 2×25564681² = 1307105829263522, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25564681.

It is not a weakly prime, because it can be changed into another prime (25561681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12782340 + 12782341.

It is an arithmetic number, because the mean of its divisors is an integer number (12782341).

Almost surely, 2^25564681 is an apocalyptic number.

It is an amenable number.

25564681 is a deficient number, since it is larger than the sum of its proper divisors (1).

25564681 is an equidigital number, since it uses as much as digits as its factorization.

25564681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 57600, while the sum is 37.

The square root of 25564681 is about 5056.1527864573. The cubic root of 25564681 is about 294.5869196905.

The spelling of 25564681 in words is "twenty-five million, five hundred sixty-four thousand, six hundred eighty-one".