21343401617 has 2 divisors, whose sum is σ = 21343401618. Its totient is φ = 21343401616.

The previous prime is 21343401559. The next prime is 21343401631. The reversal of 21343401617 is 71610434312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20234778001 + 1108623616 = 142249^2 + 33296^2 .

It is a cyclic number.

It is not a de Polignac number, because 21343401617 - 2¹² = 21343397521 is a prime.

It is not a weakly prime, because it can be changed into another prime (21343401647) 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 as a sum of consecutive naturals, namely, 10671700808 + 10671700809.

It is an arithmetic number, because the mean of its divisors is an integer number (10671700809).

Almost surely, 2^21343401617 is an apocalyptic number.

It is an amenable number.

21343401617 is a deficient number, since it is larger than the sum of its proper divisors (1).

21343401617 is an equidigital number, since it uses as much as digits as its factorization.

21343401617 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 32.

Adding to 21343401617 its reverse (71610434312), we get a palindrome (92953835929).

The spelling of 21343401617 in words is "twenty-one billion, three hundred forty-three million, four hundred one thousand, six hundred seventeen".