21012327 has 72 divisors (see below), whose sum is σ = 38413440. Its totient is φ = 11007360.

The previous prime is 21012311. The next prime is 21012331. The reversal of 21012327 is 72321012.

21012327 is nontrivially palindromic in base 5.

It is not a de Polignac number, because 21012327 - 2⁴ = 21012311 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012307) 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 71 ways as a sum of consecutive naturals, for example, 396433 + ... + 396485.

It is an arithmetic number, because the mean of its divisors is an integer number (533520).

Almost surely, 2^21012327 is an apocalyptic number.

21012327 is a deficient number, since it is larger than the sum of its proper divisors (17401113).

21012327 is a wasteful number, since it uses less digits than its factorization.

21012327 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 21012327 is about 4583.9204836035. The cubic root of 21012327 is about 275.9463900286.

Adding to 21012327 its reverse (72321012), we get a palindrome (93333339).

The spelling of 21012327 in words is "twenty-one million, twelve thousand, three hundred twenty-seven".