21716159 has 2 divisors, whose sum is σ = 21716160. Its totient is φ = 21716158.

The previous prime is 21716143. The next prime is 21716237. The reversal of 21716159 is 95161712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21716159 - 2⁴ = 21716143 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 (21716659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10858079 + 10858080.

It is an arithmetic number, because the mean of its divisors is an integer number (10858080).

Almost surely, 2^21716159 is an apocalyptic number.

21716159 is a deficient number, since it is larger than the sum of its proper divisors (1).

21716159 is an equidigital number, since it uses as much as digits as its factorization.

21716159 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3780, while the sum is 32.

The square root of 21716159 is about 4660.0599781548. The cubic root of 21716159 is about 278.9936621505.

The spelling of 21716159 in words is "twenty-one million, seven hundred sixteen thousand, one hundred fifty-nine".