821743411109 has 2 divisors, whose sum is σ = 821743411110. Its totient is φ = 821743411108.

The previous prime is 821743411103. The next prime is 821743411133. The reversal of 821743411109 is 901114347128.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 588169354084 + 233574057025 = 766922^2 + 483295^2 .

It is a cyclic number.

It is not a de Polignac number, because 821743411109 - 2²⁰ = 821742362533 is a prime.

It is a super-3 number, since 3×821743411109³ (a number of 37 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (821743411103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410871705554 + 410871705555.

It is an arithmetic number, because the mean of its divisors is an integer number (410871705555).

Almost surely, 2^821743411109 is an apocalyptic number.

It is an amenable number.

821743411109 is a deficient number, since it is larger than the sum of its proper divisors (1).

821743411109 is an equidigital number, since it uses as much as digits as its factorization.

821743411109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48384, while the sum is 41.

The spelling of 821743411109 in words is "eight hundred twenty-one billion, seven hundred forty-three million, four hundred eleven thousand, one hundred nine".