25481278481 has 2 divisors, whose sum is σ = 25481278482. Its totient is φ = 25481278480.

The previous prime is 25481278447. The next prime is 25481278489. The reversal of 25481278481 is 18487218452.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22344270400 + 3137008081 = 149480^2 + 56009^2 .

It is a cyclic number.

It is not a de Polignac number, because 25481278481 - 2¹⁰ = 25481277457 is a prime.

It is a super-2 number, since 2×25481278481² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (25481278489) 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, 12740639240 + 12740639241.

It is an arithmetic number, because the mean of its divisors is an integer number (12740639241).

Almost surely, 2^25481278481 is an apocalyptic number.

It is an amenable number.

25481278481 is a deficient number, since it is larger than the sum of its proper divisors (1).

25481278481 is an equidigital number, since it uses as much as digits as its factorization.

25481278481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1146880, while the sum is 50.

The spelling of 25481278481 in words is "twenty-five billion, four hundred eighty-one million, two hundred seventy-eight thousand, four hundred eighty-one".