21536227 has 4 divisors (see below), whose sum is σ = 22230976. Its totient is φ = 20841480.

The previous prime is 21536213. The next prime is 21536261. The reversal of 21536227 is 72263512.

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 21536227 - 2¹¹ = 21534179 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21536195 and 21536204.

It is not an unprimeable number, because it can be changed into a prime (21536267) 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, 347328 + ... + 347389.

It is an arithmetic number, because the mean of its divisors is an integer number (5557744).

Almost surely, 2^21536227 is an apocalyptic number.

21536227 is a deficient number, since it is larger than the sum of its proper divisors (694749).

21536227 is an equidigital number, since it uses as much as digits as its factorization.

21536227 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 694748.

The product of its digits is 5040, while the sum is 28.

The square root of 21536227 is about 4640.7140614349. The cubic root of 21536227 is about 278.2209783129.

Adding to 21536227 its reverse (72263512), we get a palindrome (93799739).

The spelling of 21536227 in words is "twenty-one million, five hundred thirty-six thousand, two hundred twenty-seven".