20998163 has 2 divisors, whose sum is σ = 20998164. Its totient is φ = 20998162.

The previous prime is 20998157. The next prime is 20998169. The reversal of 20998163 is 36189902.

It is a balanced prime because it is at equal distance from previous prime (20998157) and next prime (20998169).

It is a cyclic number.

It is not a de Polignac number, because 20998163 - 2¹⁰ = 20997139 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20998169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10499081 + 10499082.

It is an arithmetic number, because the mean of its divisors is an integer number (10499082).

Almost surely, 2^20998163 is an apocalyptic number.

20998163 is a deficient number, since it is larger than the sum of its proper divisors (1).

20998163 is an equidigital number, since it uses as much as digits as its factorization.

20998163 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 20998163 is about 4582.3752574402. The cubic root of 20998163 is about 275.8843727310.

The spelling of 20998163 in words is "twenty million, nine hundred ninety-eight thousand, one hundred sixty-three".