21143140217 has 2 divisors, whose sum is σ = 21143140218. Its totient is φ = 21143140216.

The previous prime is 21143140201. The next prime is 21143140243. The reversal of 21143140217 is 71204134112.

It is an a-pointer prime, because the next prime (21143140243) can be obtained adding 21143140217 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16257270016 + 4885870201 = 127504^2 + 69899^2 .

It is a cyclic number.

It is not a de Polignac number, because 21143140217 - 2⁴ = 21143140201 is a prime.

It is not a weakly prime, because it can be changed into another prime (21143142217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571570108 + 10571570109.

It is an arithmetic number, because the mean of its divisors is an integer number (10571570109).

Almost surely, 2^21143140217 is an apocalyptic number.

It is an amenable number.

21143140217 is a deficient number, since it is larger than the sum of its proper divisors (1).

21143140217 is an equidigital number, since it uses as much as digits as its factorization.

21143140217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344, while the sum is 26.

Adding to 21143140217 its reverse (71204134112), we get a palindrome (92347274329).

The spelling of 21143140217 in words is "twenty-one billion, one hundred forty-three million, one hundred forty thousand, two hundred seventeen".