21688770711 has 4 divisors (see below), whose sum is σ = 28918360952. Its totient is φ = 14459180472.

The previous prime is 21688770707. The next prime is 21688770737. The reversal of 21688770711 is 11707788612.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21688770711 - 2² = 21688770707 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21688770791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3614795116 + ... + 3614795121.

It is an arithmetic number, because the mean of its divisors is an integer number (7229590238).

Almost surely, 2^21688770711 is an apocalyptic number.

21688770711 is a deficient number, since it is larger than the sum of its proper divisors (7229590241).

21688770711 is an equidigital number, since it uses as much as digits as its factorization.

21688770711 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7229590240.

The product of its (nonzero) digits is 263424, while the sum is 48.

The spelling of 21688770711 in words is "twenty-one billion, six hundred eighty-eight million, seven hundred seventy thousand, seven hundred eleven".