25391689 has 2 divisors, whose sum is σ = 25391690. Its totient is φ = 25391688.

The previous prime is 25391647. The next prime is 25391699. The reversal of 25391689 is 98619352.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15936064 + 9455625 = 3992^2 + 3075^2 .

It is a cyclic number.

It is not a de Polignac number, because 25391689 - 2¹⁷ = 25260617 is a prime.

It is not a weakly prime, because it can be changed into another prime (25391699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12695844 + 12695845.

It is an arithmetic number, because the mean of its divisors is an integer number (12695845).

Almost surely, 2^25391689 is an apocalyptic number.

It is an amenable number.

25391689 is a deficient number, since it is larger than the sum of its proper divisors (1).

25391689 is an equidigital number, since it uses as much as digits as its factorization.

25391689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116640, while the sum is 43.

The square root of 25391689 is about 5039.0166699466. The cubic root of 25391689 is about 293.9209414587.

The spelling of 25391689 in words is "twenty-five million, three hundred ninety-one thousand, six hundred eighty-nine".