25721741203217 has 2 divisors, whose sum is σ = 25721741203218. Its totient is φ = 25721741203216.

The previous prime is 25721741203187. The next prime is 25721741203259. The reversal of 25721741203217 is 71230214712752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24373613537296 + 1348127665921 = 4936964^2 + 1161089^2 .

It is a cyclic number.

It is not a de Polignac number, because 25721741203217 - 2⁶ = 25721741203153 is a prime.

It is a super-2 number, since 2×25721741203217² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25721741203297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12860870601608 + 12860870601609.

It is an arithmetic number, because the mean of its divisors is an integer number (12860870601609).

Almost surely, 2^{25721741203217} is an apocalyptic number.

It is an amenable number.

25721741203217 is a deficient number, since it is larger than the sum of its proper divisors (1).

25721741203217 is an equidigital number, since it uses as much as digits as its factorization.

25721741203217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 329280, while the sum is 44.

Adding to 25721741203217 its reverse (71230214712752), we get a palindrome (96951955915969).

The spelling of 25721741203217 in words is "twenty-five trillion, seven hundred twenty-one billion, seven hundred forty-one million, two hundred three thousand, two hundred seventeen".