21026163 has 12 divisors (see below), whose sum is σ = 29309000. Its totient is φ = 13406976.

The previous prime is 21026149. The next prime is 21026171. The reversal of 21026163 is 36162012.

It is a happy number.

It is not a de Polignac number, because 21026163 - 2⁴ = 21026147 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21026143) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5038 + ... + 8211.

Almost surely, 2^21026163 is an apocalyptic number.

21026163 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21026163 is a deficient number, since it is larger than the sum of its proper divisors (8282837).

21026163 is a wasteful number, since it uses less digits than its factorization.

21026163 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13298 (or 13275 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 21026163 is about 4585.4294237290. The cubic root of 21026163 is about 276.0069442697.

Adding to 21026163 its reverse (36162012), we get a palindrome (57188175).

The spelling of 21026163 in words is "twenty-one million, twenty-six thousand, one hundred sixty-three".