25730521 has 2 divisors, whose sum is σ = 25730522. Its totient is φ = 25730520.

The previous prime is 25730519. The next prime is 25730531. The reversal of 25730521 is 12503752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15713296 + 10017225 = 3964^2 + 3165^2 .

It is a cyclic number.

It is not a de Polignac number, because 25730521 - 2¹ = 25730519 is a prime.

Together with 25730519, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (25730531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12865260 + 12865261.

It is an arithmetic number, because the mean of its divisors is an integer number (12865261).

Almost surely, 2^25730521 is an apocalyptic number.

It is an amenable number.

25730521 is a deficient number, since it is larger than the sum of its proper divisors (1).

25730521 is an equidigital number, since it uses as much as digits as its factorization.

25730521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 25730521 is about 5072.5260965322. The cubic root of 25730521 is about 295.2225496749. Note that the first 3 decimals are identical.

The spelling of 25730521 in words is "twenty-five million, seven hundred thirty thousand, five hundred twenty-one".