21327747 has 16 divisors (see below), whose sum is σ = 34210560. Its totient is φ = 11545632.

The previous prime is 21327727. The next prime is 21327751. The reversal of 21327747 is 74772312.

It is not a de Polignac number, because 21327747 - 2¹² = 21323651 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21327727) 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 15 ways as a sum of consecutive naturals, for example, 26328 + ... + 27125.

It is an arithmetic number, because the mean of its divisors is an integer number (2138160).

Almost surely, 2^21327747 is an apocalyptic number.

21327747 is a deficient number, since it is larger than the sum of its proper divisors (12882813).

21327747 is a wasteful number, since it uses less digits than its factorization.

21327747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53482.

The product of its digits is 16464, while the sum is 33.

The square root of 21327747 is about 4618.1973756001. The cubic root of 21327747 is about 277.3202992069.

The spelling of 21327747 in words is "twenty-one million, three hundred twenty-seven thousand, seven hundred forty-seven".