21766367611 has 2 divisors, whose sum is σ = 21766367612. Its totient is φ = 21766367610.

The previous prime is 21766367569. The next prime is 21766367663. The reversal of 21766367611 is 11676366712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21766367611 - 2⁹ = 21766367099 is a prime.

It is not a weakly prime, because it can be changed into another prime (21766367011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10883183805 + 10883183806.

It is an arithmetic number, because the mean of its divisors is an integer number (10883183806).

Almost surely, 2^21766367611 is an apocalyptic number.

21766367611 is a deficient number, since it is larger than the sum of its proper divisors (1).

21766367611 is an equidigital number, since it uses as much as digits as its factorization.

21766367611 is an evil number, because the sum of its binary digits is even.

The product of its digits is 381024, while the sum is 46.

The spelling of 21766367611 in words is "twenty-one billion, seven hundred sixty-six million, three hundred sixty-seven thousand, six hundred eleven".