25691389 has 2 divisors, whose sum is σ = 25691390. Its totient is φ = 25691388.

The previous prime is 25691381. The next prime is 25691411. The reversal of 25691389 is 98319652.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25674489 + 16900 = 5067^2 + 130^2 .

It is a cyclic number.

It is not a de Polignac number, because 25691389 - 2³ = 25691381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25691381) 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, 12845694 + 12845695.

It is an arithmetic number, because the mean of its divisors is an integer number (12845695).

Almost surely, 2^25691389 is an apocalyptic number.

It is an amenable number.

25691389 is a deficient number, since it is larger than the sum of its proper divisors (1).

25691389 is an equidigital number, since it uses as much as digits as its factorization.

25691389 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 25691389 is about 5068.6673791047. The cubic root of 25691389 is about 295.0728116739.

The spelling of 25691389 in words is "twenty-five million, six hundred ninety-one thousand, three hundred eighty-nine".