21316028 has 12 divisors (see below), whose sum is σ = 39497472. Its totient is φ = 10031040.

The previous prime is 21316027. The next prime is 21316037. The reversal of 21316028 is 82061312.

It is a junction number, because it is equal to n+sod(n) for n = 21315994 and 21316012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21316021) 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 3 ways as a sum of consecutive naturals, for example, 156668 + ... + 156803.

It is an arithmetic number, because the mean of its divisors is an integer number (3291456).

Almost surely, 2^21316028 is an apocalyptic number.

It is an amenable number.

21316028 is a deficient number, since it is larger than the sum of its proper divisors (18181444).

21316028 is a wasteful number, since it uses less digits than its factorization.

21316028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313492 (or 313490 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 21316028 is about 4616.9284161659. The cubic root of 21316028 is about 277.2694966535.

The spelling of 21316028 in words is "twenty-one million, three hundred sixteen thousand, twenty-eight".