20398243 has 2 divisors, whose sum is σ = 20398244. Its totient is φ = 20398242.

The previous prime is 20398241. The next prime is 20398277. The reversal of 20398243 is 34289302.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20398243 - 2¹ = 20398241 is a prime.

Together with 20398241, it forms a pair of twin primes.

It is equal to p_1294258 and since 20398243 and 1294258 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (20398241) 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, 10199121 + 10199122.

It is an arithmetic number, because the mean of its divisors is an integer number (10199122).

Almost surely, 2^20398243 is an apocalyptic number.

20398243 is a deficient number, since it is larger than the sum of its proper divisors (1).

20398243 is an equidigital number, since it uses as much as digits as its factorization.

20398243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 20398243 is about 4516.4414088971. The cubic root of 20398243 is about 273.2315969120.

The spelling of 20398243 in words is "twenty million, three hundred ninety-eight thousand, two hundred forty-three".