25721147 has 2 divisors, whose sum is σ = 25721148. Its totient is φ = 25721146.

The previous prime is 25721071. The next prime is 25721167. The reversal of 25721147 is 74112752.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25721147 - 2¹⁶ = 25655611 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (25721167) 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, 12860573 + 12860574.

It is an arithmetic number, because the mean of its divisors is an integer number (12860574).

Almost surely, 2^25721147 is an apocalyptic number.

25721147 is a deficient number, since it is larger than the sum of its proper divisors (1).

25721147 is an equidigital number, since it uses as much as digits as its factorization.

25721147 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3920, while the sum is 29.

The square root of 25721147 is about 5071.6020151427. The cubic root of 25721147 is about 295.1866940424.

Adding to 25721147 its reverse (74112752), we get a palindrome (99833899).

The spelling of 25721147 in words is "twenty-five million, seven hundred twenty-one thousand, one hundred forty-seven".