21688143241 has 2 divisors, whose sum is σ = 21688143242. Its totient is φ = 21688143240.

The previous prime is 21688143163. The next prime is 21688143247. The reversal of 21688143241 is 14234188612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14400960016 + 7287183225 = 120004^2 + 85365^2 .

It is a cyclic number.

It is not a de Polignac number, because 21688143241 - 2¹¹ = 21688141193 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21688143194 and 21688143203.

It is not a weakly prime, because it can be changed into another prime (21688143247) 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, 10844071620 + 10844071621.

It is an arithmetic number, because the mean of its divisors is an integer number (10844071621).

Almost surely, 2^21688143241 is an apocalyptic number.

It is an amenable number.

21688143241 is a deficient number, since it is larger than the sum of its proper divisors (1).

21688143241 is an equidigital number, since it uses as much as digits as its factorization.

21688143241 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 73728, while the sum is 40.

The spelling of 21688143241 in words is "twenty-one billion, six hundred eighty-eight million, one hundred forty-three thousand, two hundred forty-one".