25488765849581 has 2 divisors, whose sum is σ = 25488765849582. Its totient is φ = 25488765849580.

The previous prime is 25488765849553. The next prime is 25488765849601. The reversal of 25488765849581 is 18594856788452.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17910120241225 + 7578645608356 = 4232035^2 + 2752934^2 .

It is a cyclic number.

It is not a de Polignac number, because 25488765849581 - 2⁴² = 21090719338477 is a prime.

It is a super-2 number, since 2×25488765849581² (a number of 28 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 25488765849496 and 25488765849505.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25488765845581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12744382924790 + 12744382924791.

It is an arithmetic number, because the mean of its divisors is an integer number (12744382924791).

Almost surely, 2^{25488765849581} is an apocalyptic number.

It is an amenable number.

25488765849581 is a deficient number, since it is larger than the sum of its proper divisors (1).

25488765849581 is an equidigital number, since it uses as much as digits as its factorization.

25488765849581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6193152000, while the sum is 80.

The spelling of 25488765849581 in words is "twenty-five trillion, four hundred eighty-eight billion, seven hundred sixty-five million, eight hundred forty-nine thousand, five hundred eighty-one".