25320521457817 has 2 divisors, whose sum is σ = 25320521457818. Its totient is φ = 25320521457816.

The previous prime is 25320521457769. The next prime is 25320521457821. The reversal of 25320521457817 is 71875412502352.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25112716765081 + 207804692736 = 5011259^2 + 455856^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25320521457817 is a prime.

It is a super-2 number, since 2×25320521457817² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25320521457017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12660260728908 + 12660260728909.

It is an arithmetic number, because the mean of its divisors is an integer number (12660260728909).

Almost surely, 2^{25320521457817} is an apocalyptic number.

It is an amenable number.

25320521457817 is a deficient number, since it is larger than the sum of its proper divisors (1).

25320521457817 is an equidigital number, since it uses as much as digits as its factorization.

25320521457817 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4704000, while the sum is 52.

The spelling of 25320521457817 in words is "twenty-five trillion, three hundred twenty billion, five hundred twenty-one million, four hundred fifty-seven thousand, eight hundred seventeen".