21765849711 has 4 divisors (see below), whose sum is σ = 29021132952. Its totient is φ = 14510566472.

The previous prime is 21765849641. The next prime is 21765849731. The reversal of 21765849711 is 11794856712.

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

It is a cyclic number.

It is not a de Polignac number, because 21765849711 - 2²² = 21761655407 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21765849731) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3627641616 + ... + 3627641621.

It is an arithmetic number, because the mean of its divisors is an integer number (7255283238).

Almost surely, 2^21765849711 is an apocalyptic number.

21765849711 is a deficient number, since it is larger than the sum of its proper divisors (7255283241).

21765849711 is an equidigital number, since it uses as much as digits as its factorization.

21765849711 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7255283240.

The product of its digits is 846720, while the sum is 51.

The spelling of 21765849711 in words is "twenty-one billion, seven hundred sixty-five million, eight hundred forty-nine thousand, seven hundred eleven".