21686868367 has 2 divisors, whose sum is σ = 21686868368. Its totient is φ = 21686868366.

The previous prime is 21686868341. The next prime is 21686868373. The reversal of 21686868367 is 76386868612.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21686868367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21686868317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10843434183 + 10843434184.

It is an arithmetic number, because the mean of its divisors is an integer number (10843434184).

Almost surely, 2^21686868367 is an apocalyptic number.

21686868367 is a deficient number, since it is larger than the sum of its proper divisors (1).

21686868367 is an equidigital number, since it uses as much as digits as its factorization.

21686868367 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27869184, while the sum is 61.

The spelling of 21686868367 in words is "twenty-one billion, six hundred eighty-six million, eight hundred sixty-eight thousand, three hundred sixty-seven".