11655135581 has 2 divisors, whose sum is σ = 11655135582. Its totient is φ = 11655135580.

The previous prime is 11655135571. The next prime is 11655135599. The reversal of 11655135581 is 18553155611.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6539309956 + 5115825625 = 80866^2 + 71525^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11655135581 is a prime.

It is a super-2 number, since 2×11655135581² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11655135551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5827567790 + 5827567791.

It is an arithmetic number, because the mean of its divisors is an integer number (5827567791).

Almost surely, 2^11655135581 is an apocalyptic number.

It is an amenable number.

11655135581 is a deficient number, since it is larger than the sum of its proper divisors (1).

11655135581 is an equidigital number, since it uses as much as digits as its factorization.

11655135581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90000, while the sum is 41.

The spelling of 11655135581 in words is "eleven billion, six hundred fifty-five million, one hundred thirty-five thousand, five hundred eighty-one".