21106775243 has 2 divisors, whose sum is σ = 21106775244. Its totient is φ = 21106775242.

The previous prime is 21106775219. The next prime is 21106775269. The reversal of 21106775243 is 34257760112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21106775243 is a prime.

It is a super-2 number, since 2×21106775243² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21106775197 and 21106775206.

It is not a weakly prime, because it can be changed into another prime (21106775143) 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 as a sum of consecutive naturals, namely, 10553387621 + 10553387622.

It is an arithmetic number, because the mean of its divisors is an integer number (10553387622).

Almost surely, 2^21106775243 is an apocalyptic number.

21106775243 is a deficient number, since it is larger than the sum of its proper divisors (1).

21106775243 is an equidigital number, since it uses as much as digits as its factorization.

21106775243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 70560, while the sum is 38.

The spelling of 21106775243 in words is "twenty-one billion, one hundred six million, seven hundred seventy-five thousand, two hundred forty-three".