21017159 has 2 divisors, whose sum is σ = 21017160. Its totient is φ = 21017158.

The previous prime is 21017149. The next prime is 21017167. The reversal of 21017159 is 95171012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21017159 - 2⁸ = 21016903 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 (21017149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10508579 + 10508580.

It is an arithmetic number, because the mean of its divisors is an integer number (10508580).

Almost surely, 2^21017159 is an apocalyptic number.

21017159 is a deficient number, since it is larger than the sum of its proper divisors (1).

21017159 is an equidigital number, since it uses as much as digits as its factorization.

21017159 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 630, while the sum is 26.

The square root of 21017159 is about 4584.4475130598. The cubic root of 21017159 is about 275.9675406412.

The spelling of 21017159 in words is "twenty-one million, seventeen thousand, one hundred fifty-nine".