21026463 has 16 divisors (see below), whose sum is σ = 29223936. Its totient is φ = 13432320.

The previous prime is 21026443. The next prime is 21026477. The reversal of 21026463 is 36462012.

It is not a de Polignac number, because 21026463 - 2⁵ = 21026431 is a prime.

It is a super-2 number, since 2×21026463² = 884224292580738, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21026443) 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 in 15 ways as a sum of consecutive naturals, for example, 8895 + ... + 11007.

It is an arithmetic number, because the mean of its divisors is an integer number (1826496).

Almost surely, 2^21026463 is an apocalyptic number.

21026463 is a deficient number, since it is larger than the sum of its proper divisors (8197473).

21026463 is a wasteful number, since it uses less digits than its factorization.

21026463 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2254.

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 21026463 is about 4585.4621359248. The cubic root of 21026463 is about 276.0082569468.

Adding to 21026463 its reverse (36462012), we get a palindrome (57488475).

The spelling of 21026463 in words is "twenty-one million, twenty-six thousand, four hundred sixty-three".