21768346679 has 2 divisors, whose sum is σ = 21768346680. Its totient is φ = 21768346678.

The previous prime is 21768346669. The next prime is 21768346693. The reversal of 21768346679 is 97664386712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21768346679 - 2⁸ = 21768346423 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21768346669) 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, 10884173339 + 10884173340.

It is an arithmetic number, because the mean of its divisors is an integer number (10884173340).

Almost surely, 2^21768346679 is an apocalyptic number.

21768346679 is a deficient number, since it is larger than the sum of its proper divisors (1).

21768346679 is an equidigital number, since it uses as much as digits as its factorization.

21768346679 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18289152, while the sum is 59.

The spelling of 21768346679 in words is "twenty-one billion, seven hundred sixty-eight million, three hundred forty-six thousand, six hundred seventy-nine".