21711143 has 2 divisors, whose sum is σ = 21711144. Its totient is φ = 21711142.

The previous prime is 21711127. The next prime is 21711163. The reversal of 21711143 is 34111712.

It is a happy number.

It is an a-pointer prime, because the next prime (21711163) can be obtained adding 21711143 to its sum of digits (20).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21711143 - 2⁴ = 21711127 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21711163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10855571 + 10855572.

It is an arithmetic number, because the mean of its divisors is an integer number (10855572).

Almost surely, 2^21711143 is an apocalyptic number.

21711143 is a deficient number, since it is larger than the sum of its proper divisors (1).

21711143 is an equidigital number, since it uses as much as digits as its factorization.

21711143 is an evil number, because the sum of its binary digits is even.

The product of its digits is 168, while the sum is 20.

The square root of 21711143 is about 4659.5217565755. The cubic root of 21711143 is about 278.9721798376.

Adding to 21711143 its reverse (34111712), we get a palindrome (55822855).

The spelling of 21711143 in words is "twenty-one million, seven hundred eleven thousand, one hundred forty-three".