21017179 has 2 divisors, whose sum is σ = 21017180. Its totient is φ = 21017178.

The previous prime is 21017167. The next prime is 21017189. The reversal of 21017179 is 97171012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21017179 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21017149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10508589 + 10508590.

It is an arithmetic number, because the mean of its divisors is an integer number (10508590).

Almost surely, 2^21017179 is an apocalyptic number.

21017179 is a deficient number, since it is larger than the sum of its proper divisors (1).

21017179 is an equidigital number, since it uses as much as digits as its factorization.

21017179 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 882, while the sum is 28.

The square root of 21017179 is about 4584.4496943472. The cubic root of 21017179 is about 275.9676281784.

The spelling of 21017179 in words is "twenty-one million, seventeen thousand, one hundred seventy-nine".