21122783375909 has 2 divisors, whose sum is σ = 21122783375910. Its totient is φ = 21122783375908.

The previous prime is 21122783375887. The next prime is 21122783375929. The reversal of 21122783375909 is 90957338722112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17678871390625 + 3443911985284 = 4204625^2 + 1855778^2 .

It is a cyclic number.

It is not a de Polignac number, because 21122783375909 - 2⁸ = 21122783375653 is a prime.

It is a super-2 number, since 2×21122783375909² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21122783375929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561391687954 + 10561391687955.

It is an arithmetic number, because the mean of its divisors is an integer number (10561391687955).

Almost surely, 2^{21122783375909} is an apocalyptic number.

It is an amenable number.

21122783375909 is a deficient number, since it is larger than the sum of its proper divisors (1).

21122783375909 is an equidigital number, since it uses as much as digits as its factorization.

21122783375909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11430720, while the sum is 59.

The spelling of 21122783375909 in words is "twenty-one trillion, one hundred twenty-two billion, seven hundred eighty-three million, three hundred seventy-five thousand, nine hundred nine".