21106775061 has 6 divisors (see below), whose sum is σ = 30487563990. Its totient is φ = 14071183368.

The previous prime is 21106775029. The next prime is 21106775083. The reversal of 21106775061 is 16057760112.

It can be written as a sum of positive squares in only one way, i.e., 20844140625 + 262634436 = 144375^2 + 16206^2 .

It is not a de Polignac number, because 21106775061 - 2⁵ = 21106775029 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21106775161) by changing a digit.

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 in 5 ways as a sum of consecutive naturals, for example, 1172598606 + ... + 1172598623.

It is an arithmetic number, because the mean of its divisors is an integer number (5081260665).

Almost surely, 2^21106775061 is an apocalyptic number.

It is an amenable number.

21106775061 is a deficient number, since it is larger than the sum of its proper divisors (9380788929).

21106775061 is a wasteful number, since it uses less digits than its factorization.

21106775061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2345197235 (or 2345197232 counting only the distinct ones).

The product of its (nonzero) digits is 17640, while the sum is 36.

The spelling of 21106775061 in words is "twenty-one billion, one hundred six million, seven hundred seventy-five thousand, sixty-one".