25640418389 has 2 divisors, whose sum is σ = 25640418390. Its totient is φ = 25640418388.

The previous prime is 25640418383. The next prime is 25640418413. The reversal of 25640418389 is 98381404652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22878075025 + 2762343364 = 151255^2 + 52558^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25640418389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25640418383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12820209194 + 12820209195.

It is an arithmetic number, because the mean of its divisors is an integer number (12820209195).

Almost surely, 2^25640418389 is an apocalyptic number.

It is an amenable number.

25640418389 is a deficient number, since it is larger than the sum of its proper divisors (1).

25640418389 is an equidigital number, since it uses as much as digits as its factorization.

25640418389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1658880, while the sum is 50.

The spelling of 25640418389 in words is "twenty-five billion, six hundred forty million, four hundred eighteen thousand, three hundred eighty-nine".