13256451365481 has 135 divisors (see below), whose sum is σ = 21488499866911. Its totient is φ = 8142658707456.

The previous prime is 13256451365461. The next prime is 13256451365513. The reversal of 13256451365481 is 18456315465231.

The square root of 13256451365481 is 3640941.

It is a perfect power (a square), and thus also a powerful number.

13256451365481 is a `hidden beast` number, since 1 + 3 + 2 + 5 + 64 + 5 + 1 + 36 + 548 + 1 = 666.

It can be written as a sum of positive squares in 13 ways, for example, as 292563073881 + 12963888291600 = 540891^2 + 3600540^2 .

It is not a de Polignac number, because 13256451365481 - 2⁵ = 13256451365449 is a prime.

It is a super-2 number, since 2×13256451365481² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13256451365441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 29524390345 + ... + 29524390793.

Almost surely, 2^{13256451365481} is an apocalyptic number.

13256451365481 is the 3640941-st square number.

13256451365481 is the 1820471-st centered octagonal number.

It is an amenable number.

13256451365481 is a deficient number, since it is larger than the sum of its proper divisors (8232048501430).

13256451365481 is an frugal number, since it uses more digits than its factorization.

13256451365481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1050 (or 522 counting only the distinct ones).

The product of its digits is 10368000, while the sum is 54.

The spelling of 13256451365481 in words is "thirteen trillion, two hundred fifty-six billion, four hundred fifty-one million, three hundred sixty-five thousand, four hundred eighty-one".