21026484 has 108 divisors (see below), whose sum is σ = 59002944. Its totient is φ = 6306048.

The previous prime is 21026477. The next prime is 21026497. The reversal of 21026484 is 48462012.

21026484 is a `hidden beast` number, since 2 + 10 + 2 + 648 + 4 = 666.

It is a super-2 number, since 2×21026484² = 884226058804512, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 in 35 ways as a sum of consecutive naturals, for example, 447349 + ... + 447395.

Almost surely, 2^21026484 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21026484, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29501472).

21026484 is an abundant number, since it is smaller than the sum of its proper divisors (37976460).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21026484 is a wasteful number, since it uses less digits than its factorization.

21026484 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 21026484 is about 4585.4644257698. The cubic root of 21026484 is about 276.0083488338.

Adding to 21026484 its reverse (48462012), we get a palindrome (69488496).

Subtracting 21026484 from its reverse (48462012), we obtain a triangular number (27435528 = T₇₄₀₇).

The spelling of 21026484 in words is "twenty-one million, twenty-six thousand, four hundred eighty-four".