11217581761 has 2 divisors, whose sum is σ = 11217581762. Its totient is φ = 11217581760.

The previous prime is 11217581759. The next prime is 11217581797. The reversal of 11217581761 is 16718571211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11160654736 + 56927025 = 105644^2 + 7545^2 .

It is a cyclic number.

It is not a de Polignac number, because 11217581761 - 2¹ = 11217581759 is a prime.

It is a super-2 number, since 2×11217581761² (a number of 21 digits) contains 22 as substring.

Together with 11217581759, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (11217581701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5608790880 + 5608790881.

It is an arithmetic number, because the mean of its divisors is an integer number (5608790881).

Almost surely, 2^11217581761 is an apocalyptic number.

It is an amenable number.

11217581761 is a deficient number, since it is larger than the sum of its proper divisors (1).

11217581761 is an equidigital number, since it uses as much as digits as its factorization.

11217581761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23520, while the sum is 40.

The spelling of 11217581761 in words is "eleven billion, two hundred seventeen million, five hundred eighty-one thousand, seven hundred sixty-one".