20823169 has 2 divisors, whose sum is σ = 20823170. Its totient is φ = 20823168.

The previous prime is 20823167. The next prime is 20823239. The reversal of 20823169 is 96132802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19847025 + 976144 = 4455^2 + 988^2 .

It is a cyclic number.

It is not a de Polignac number, because 20823169 - 2¹ = 20823167 is a prime.

It is a super-2 number, since 2×20823169² = 867208734405122, which contains 22 as substring.

Together with 20823167, it forms a pair of twin primes.

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 20823169.

It is not a weakly prime, because it can be changed into another prime (20823167) 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, 10411584 + 10411585.

It is an arithmetic number, because the mean of its divisors is an integer number (10411585).

Almost surely, 2^20823169 is an apocalyptic number.

It is an amenable number.

20823169 is a deficient number, since it is larger than the sum of its proper divisors (1).

20823169 is an equidigital number, since it uses as much as digits as its factorization.

20823169 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 20823169 is about 4563.2410631042. The cubic root of 20823169 is about 275.1158476094.

The spelling of 20823169 in words is "twenty million, eight hundred twenty-three thousand, one hundred sixty-nine".