20571169 has 2 divisors, whose sum is σ = 20571170. Its totient is φ = 20571168.

The previous prime is 20571163. The next prime is 20571209. The reversal of 20571169 is 96117502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20142144 + 429025 = 4488^2 + 655^2 .

It is a cyclic number.

It is not a de Polignac number, because 20571169 - 2⁵ = 20571137 is a prime.

It is a super-2 number, since 2×20571169² = 846345988053122, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20571169.

It is not a weakly prime, because it can be changed into another prime (20571163) 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, 10285584 + 10285585.

It is an arithmetic number, because the mean of its divisors is an integer number (10285585).

Almost surely, 2^20571169 is an apocalyptic number.

It is an amenable number.

20571169 is a deficient number, since it is larger than the sum of its proper divisors (1).

20571169 is an equidigital number, since it uses as much as digits as its factorization.

20571169 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3780, while the sum is 31.

The square root of 20571169 is about 4535.5450609601. The cubic root of 20571169 is about 274.0015317726.

The spelling of 20571169 in words is "twenty million, five hundred seventy-one thousand, one hundred sixty-nine".