21284802 has 64 divisors (see below), whose sum is σ = 58982400. Its totient is φ = 5527440.

The previous prime is 21284801. The next prime is 21284839. The reversal of 21284802 is 20848212.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21284801) 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 in 31 ways as a sum of consecutive naturals, for example, 1599 + ... + 6717.

It is an arithmetic number, because the mean of its divisors is an integer number (921600).

Almost surely, 2^21284802 is an apocalyptic number.

21284802 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21284802, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29491200).

21284802 is an abundant number, since it is smaller than the sum of its proper divisors (37697598).

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

21284802 is a wasteful number, since it uses less digits than its factorization.

21284802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5148 (or 5142 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 21284802 is about 4613.5454912681. The cubic root of 21284802 is about 277.1340391396.

The spelling of 21284802 in words is "twenty-one million, two hundred eighty-four thousand, eight hundred two".