13365440881 has 9 divisors (see below), whose sum is σ = 14474264769. Its totient is φ = 12335942736.

The previous prime is 13365440873. The next prime is 13365440899. The reversal of 13365440881 is 18804456331.

The square root of 13365440881 is 115609.

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

It can be written as a sum of positive squares in 4 ways, for example, as 6862631281 + 6502809600 = 82841^2 + 80640^2 .

It is not a de Polignac number, because 13365440881 - 2³ = 13365440873 is a prime.

It is a super-2 number, since 2×13365440881² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13365440861) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1498471 + ... + 1507363.

It is an arithmetic number, because the mean of its divisors is an integer number (1608251641).

Almost surely, 2^13365440881 is an apocalyptic number.

13365440881 is the 115609-th square number.

13365440881 is the 57805-th centered octagonal number.

It is an amenable number.

13365440881 is a deficient number, since it is larger than the sum of its proper divisors (1108823888).

13365440881 is an frugal number, since it uses more digits than its factorization.

13365440881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17812 (or 8906 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 43.

The spelling of 13365440881 in words is "thirteen billion, three hundred sixty-five million, four hundred forty thousand, eight hundred eighty-one".