21323011109 has 2 divisors, whose sum is σ = 21323011110. Its totient is φ = 21323011108.

The previous prime is 21323011103. The next prime is 21323011121. The reversal of 21323011109 is 90111032312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21320380225 + 2630884 = 146015^2 + 1622^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21323011109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21323011103) 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, 10661505554 + 10661505555.

It is an arithmetic number, because the mean of its divisors is an integer number (10661505555).

Almost surely, 2^21323011109 is an apocalyptic number.

It is an amenable number.

21323011109 is a deficient number, since it is larger than the sum of its proper divisors (1).

21323011109 is an equidigital number, since it uses as much as digits as its factorization.

21323011109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 23.

The spelling of 21323011109 in words is "twenty-one billion, three hundred twenty-three million, eleven thousand, one hundred nine".