11571996217 has 2 divisors, whose sum is σ = 11571996218. Its totient is φ = 11571996216.

The previous prime is 11571996199. The next prime is 11571996229. The reversal of 11571996217 is 71269917511.

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., 11325003561 + 246992656 = 106419^2 + 15716^2 .

It is a cyclic number.

It is not a de Polignac number, because 11571996217 - 2⁷ = 11571996089 is a prime.

It is a super-2 number, since 2×11571996217² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (11571996257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5785998108 + 5785998109.

It is an arithmetic number, because the mean of its divisors is an integer number (5785998109).

Almost surely, 2^11571996217 is an apocalyptic number.

It is an amenable number.

11571996217 is a deficient number, since it is larger than the sum of its proper divisors (1).

11571996217 is an equidigital number, since it uses as much as digits as its factorization.

11571996217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 238140, while the sum is 49.

The spelling of 11571996217 in words is "eleven billion, five hundred seventy-one million, nine hundred ninety-six thousand, two hundred seventeen".