21006327 has 4 divisors (see below), whose sum is σ = 28008440. Its totient is φ = 14004216.

The previous prime is 21006311. The next prime is 21006329. The reversal of 21006327 is 72360012.

It is a happy number.

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

It is not a de Polignac number, because 21006327 - 2⁴ = 21006311 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21006329) by changing a digit.

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, 3501052 + ... + 3501057.

It is an arithmetic number, because the mean of its divisors is an integer number (7002110).

Almost surely, 2^21006327 is an apocalyptic number.

21006327 is a deficient number, since it is larger than the sum of its proper divisors (7002113).

21006327 is an equidigital number, since it uses as much as digits as its factorization.

21006327 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7002112.

The product of its (nonzero) digits is 504, while the sum is 21.

The square root of 21006327 is about 4583.2659752626. The cubic root of 21006327 is about 275.9201223373.

Adding to 21006327 its reverse (72360012), we get a palindrome (93366339).

The spelling of 21006327 in words is "twenty-one million, six thousand, three hundred twenty-seven".