11365849497581 has 2 divisors, whose sum is σ = 11365849497582. Its totient is φ = 11365849497580.

The previous prime is 11365849497571. The next prime is 11365849497589. The reversal of 11365849497581 is 18579494856311.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10525703103556 + 840146394025 = 3244334^2 + 916595^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11365849497581 is a prime.

It is a super-2 number, since 2×11365849497581² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11365849497589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5682924748790 + 5682924748791.

It is an arithmetic number, because the mean of its divisors is an integer number (5682924748791).

Almost surely, 2^{11365849497581} is an apocalyptic number.

It is an amenable number.

11365849497581 is a deficient number, since it is larger than the sum of its proper divisors (1).

11365849497581 is an equidigital number, since it uses as much as digits as its factorization.

11365849497581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 261273600, while the sum is 71.

The spelling of 11365849497581 in words is "eleven trillion, three hundred sixty-five billion, eight hundred forty-nine million, four hundred ninety-seven thousand, five hundred eighty-one".