25533549281 has 2 divisors, whose sum is σ = 25533549282. Its totient is φ = 25533549280.

The previous prime is 25533549259. The next prime is 25533549287. The reversal of 25533549281 is 18294533552.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23690135056 + 1843414225 = 153916^2 + 42935^2 .

It is a cyclic number.

It is not a de Polignac number, because 25533549281 - 2¹⁴ = 25533532897 is a prime.

It is a super-2 number, since 2×25533549281² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25533549287) 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, 12766774640 + 12766774641.

It is an arithmetic number, because the mean of its divisors is an integer number (12766774641).

Almost surely, 2^25533549281 is an apocalyptic number.

It is an amenable number.

25533549281 is a deficient number, since it is larger than the sum of its proper divisors (1).

25533549281 is an equidigital number, since it uses as much as digits as its factorization.

25533549281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296000, while the sum is 47.

The spelling of 25533549281 in words is "twenty-five billion, five hundred thirty-three million, five hundred forty-nine thousand, two hundred eighty-one".