21083628 has 12 divisors (see below), whose sum is σ = 49195160. Its totient is φ = 7027872.

The previous prime is 21083611. The next prime is 21083633. The reversal of 21083628 is 82638012.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 21083595 and 21083604.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 878473 + ... + 878496.

Almost surely, 2^21083628 is an apocalyptic number.

It is an amenable number.

21083628 is an abundant number, since it is smaller than the sum of its proper divisors (28111532).

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

21083628 is a wasteful number, since it uses less digits than its factorization.

21083628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1756976 (or 1756974 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 21083628 is about 4591.6911917070. The cubic root of 21083628 is about 276.2581600478.

It can be divided in two parts, 210 and 83628, that added together give a palindrome (83838).

The spelling of 21083628 in words is "twenty-one million, eighty-three thousand, six hundred twenty-eight".