21170159 has 2 divisors, whose sum is σ = 21170160. Its totient is φ = 21170158.

The previous prime is 21170137. The next prime is 21170207. The reversal of 21170159 is 95107112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21170159 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21170119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10585079 + 10585080.

It is an arithmetic number, because the mean of its divisors is an integer number (10585080).

Almost surely, 2^21170159 is an apocalyptic number.

21170159 is a deficient number, since it is larger than the sum of its proper divisors (1).

21170159 is an equidigital number, since it uses as much as digits as its factorization.

21170159 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 21170159 is about 4601.1041066248. The cubic root of 21170159 is about 276.6355819014.

The spelling of 21170159 in words is "twenty-one million, one hundred seventy thousand, one hundred fifty-nine".