21018163 has 2 divisors, whose sum is σ = 21018164. Its totient is φ = 21018162.

The previous prime is 21018149. The next prime is 21018167. The reversal of 21018163 is 36181012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21018163 - 2²¹ = 18921011 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is equal to p_1331059 and since 21018163 and 1331059 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 (21018167) 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, 10509081 + 10509082.

It is an arithmetic number, because the mean of its divisors is an integer number (10509082).

Almost surely, 2^21018163 is an apocalyptic number.

21018163 is a deficient number, since it is larger than the sum of its proper divisors (1).

21018163 is an equidigital number, since it uses as much as digits as its factorization.

21018163 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 21018163 is about 4584.5570124059. The cubic root of 21018163 is about 275.9719349395.

Adding to 21018163 its reverse (36181012), we get a palindrome (57199175).

The spelling of 21018163 in words is "twenty-one million, eighteen thousand, one hundred sixty-three".