25427128409 has 2 divisors, whose sum is σ = 25427128410. Its totient is φ = 25427128408.

The previous prime is 25427128403. The next prime is 25427128421. The reversal of 25427128409 is 90482172452.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24955152784 + 471975625 = 157972^2 + 21725^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25427128409 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25427128409.

It is not a weakly prime, because it can be changed into another prime (25427128403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12713564204 + 12713564205.

It is an arithmetic number, because the mean of its divisors is an integer number (12713564205).

Almost surely, 2^25427128409 is an apocalyptic number.

It is an amenable number.

25427128409 is a deficient number, since it is larger than the sum of its proper divisors (1).

25427128409 is an equidigital number, since it uses as much as digits as its factorization.

25427128409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 322560, while the sum is 44.

The spelling of 25427128409 in words is "twenty-five billion, four hundred twenty-seven million, one hundred twenty-eight thousand, four hundred nine".