20717219 has 2 divisors, whose sum is σ = 20717220. Its totient is φ = 20717218.

The previous prime is 20717209. The next prime is 20717231. The reversal of 20717219 is 91271702.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20717219 - 2⁸ = 20716963 is a prime.

It is a super-2 number, since 2×20717219² = 858406326187922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 20717191 and 20717200.

It is not a weakly prime, because it can be changed into another prime (20717209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10358609 + 10358610.

It is an arithmetic number, because the mean of its divisors is an integer number (10358610).

Almost surely, 2^20717219 is an apocalyptic number.

20717219 is a deficient number, since it is larger than the sum of its proper divisors (1).

20717219 is an equidigital number, since it uses as much as digits as its factorization.

20717219 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1764, while the sum is 29.

The square root of 20717219 is about 4551.6171851332. The cubic root of 20717219 is about 274.6484499562.

The spelling of 20717219 in words is "twenty million, seven hundred seventeen thousand, two hundred nineteen".