21766616616767 has 12 divisors (see below), whose sum is σ = 25332659302608. Its totient is φ = 18623843092800.

The previous prime is 21766616616737. The next prime is 21766616616779. The reversal of 21766616616767 is 76761661666712.

It is not a de Polignac number, because 21766616616767 - 2⁴⁰ = 20667104988991 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21766616616697 and 21766616616706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21766616616737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5290862459 + ... + 5290866572.

It is an arithmetic number, because the mean of its divisors is an integer number (2111054941884).

Almost surely, 2^{21766616616767} is an apocalyptic number.

21766616616767 is a deficient number, since it is larger than the sum of its proper divisors (3566042685841).

21766616616767 is a wasteful number, since it uses less digits than its factorization.

21766616616767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10581729070 (or 10581729059 counting only the distinct ones).

The product of its digits is 192036096, while the sum is 68.

The spelling of 21766616616767 in words is "twenty-one trillion, seven hundred sixty-six billion, six hundred sixteen million, six hundred sixteen thousand, seven hundred sixty-seven".