21107775266 has 4 divisors (see below), whose sum is σ = 31661662902. Its totient is φ = 10553887632.

The previous prime is 21107775233. The next prime is 21107775289. The reversal of 21107775266 is 66257770112.

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

It can be written as a sum of positive squares in only one way, i.e., 15544853041 + 5562922225 = 124679^2 + 74585^2 .

It is a super-2 number, since 2×21107775266² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5276943815 + ... + 5276943818.

Almost surely, 2^21107775266 is an apocalyptic number.

21107775266 is a deficient number, since it is larger than the sum of its proper divisors (10553887636).

21107775266 is a wasteful number, since it uses less digits than its factorization.

21107775266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10553887635.

The product of its (nonzero) digits is 246960, while the sum is 44.

The spelling of 21107775266 in words is "twenty-one billion, one hundred seven million, seven hundred seventy-five thousand, two hundred sixty-six".