21766406755 has 16 divisors (see below), whose sum is σ = 26287498944. Its totient is φ = 17301343360.

The previous prime is 21766406749. The next prime is 21766406803. The reversal of 21766406755 is 55760466712.

It is a de Polignac number, because none of the positive numbers 2^k-21766406755 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21766406699 and 21766406708.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2685489 + ... + 2693581.

It is an arithmetic number, because the mean of its divisors is an integer number (1642968684).

Almost surely, 2^21766406755 is an apocalyptic number.

21766406755 is a deficient number, since it is larger than the sum of its proper divisors (4521092189).

21766406755 is a wasteful number, since it uses less digits than its factorization.

21766406755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11486.

The product of its (nonzero) digits is 2116800, while the sum is 49.

The spelling of 21766406755 in words is "twenty-one billion, seven hundred sixty-six million, four hundred six thousand, seven hundred fifty-five".