21016327 has 4 divisors (see below), whose sum is σ = 21031056. Its totient is φ = 21001600.

The previous prime is 21016309. The next prime is 21016381. The reversal of 21016327 is 72361012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21016327 - 2¹⁹ = 20492039 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21016298 and 21016307.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21016397) 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, 4963 + ... + 8164.

It is an arithmetic number, because the mean of its divisors is an integer number (5257764).

Almost surely, 2^21016327 is an apocalyptic number.

21016327 is a deficient number, since it is larger than the sum of its proper divisors (14729).

21016327 is a wasteful number, since it uses less digits than its factorization.

21016327 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14728.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 21016327 is about 4584.3567705841. The cubic root of 21016327 is about 275.9638990449.

Adding to 21016327 its reverse (72361012), we get a palindrome (93377339).

The spelling of 21016327 in words is "twenty-one million, sixteen thousand, three hundred twenty-seven".