21755655711 has 12 divisors (see below), whose sum is σ = 31563274392. Its totient is φ = 14439875856.

The previous prime is 21755655707. The next prime is 21755655743. The reversal of 21755655711 is 11755655712.

21755655711 is a `hidden beast` number, since 2 + 1 + 75 + 5 + 6 + 5 + 571 + 1 = 666.

It is not a de Polignac number, because 21755655711 - 2² = 21755655707 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21755655011) 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 in 11 ways as a sum of consecutive naturals, for example, 5322396 + ... + 5326481.

It is an arithmetic number, because the mean of its divisors is an integer number (2630272866).

Almost surely, 2^21755655711 is an apocalyptic number.

21755655711 is a deficient number, since it is larger than the sum of its proper divisors (9807618681).

21755655711 is a wasteful number, since it uses less digits than its factorization.

21755655711 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10649110 (or 10649107 counting only the distinct ones).

The product of its digits is 367500, while the sum is 45.

Subtracting from 21755655711 its reverse (11755655712), we obtain a palindrome (9999999999).

The spelling of 21755655711 in words is "twenty-one billion, seven hundred fifty-five million, six hundred fifty-five thousand, seven hundred eleven".