25644139 has 2 divisors, whose sum is σ = 25644140. Its totient is φ = 25644138.

The previous prime is 25644137. The next prime is 25644169. The reversal of 25644139 is 93144652.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25644139 - 2¹ = 25644137 is a prime.

Together with 25644137, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (25644133) 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, 12822069 + 12822070.

It is an arithmetic number, because the mean of its divisors is an integer number (12822070).

Almost surely, 2^25644139 is an apocalyptic number.

25644139 is a deficient number, since it is larger than the sum of its proper divisors (1).

25644139 is an equidigital number, since it uses as much as digits as its factorization.

25644139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 34.

The square root of 25644139 is about 5064.0042456538. The cubic root of 25644139 is about 294.8918074951.

The spelling of 25644139 in words is "twenty-five million, six hundred forty-four thousand, one hundred thirty-nine".