21210227 has 2 divisors, whose sum is σ = 21210228. Its totient is φ = 21210226.

The previous prime is 21210221. The next prime is 21210269. The reversal of 21210227 is 72201212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21210227 - 2¹² = 21206131 is a prime.

It is not a weakly prime, because it can be changed into another prime (21210221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605113 + 10605114.

It is an arithmetic number, because the mean of its divisors is an integer number (10605114).

Almost surely, 2^21210227 is an apocalyptic number.

21210227 is a deficient number, since it is larger than the sum of its proper divisors (1).

21210227 is an equidigital number, since it uses as much as digits as its factorization.

21210227 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 21210227 is about 4605.4562206148. The cubic root of 21210227 is about 276.8099979891.

Adding to 21210227 its reverse (72201212), we get a palindrome (93411439).

The spelling of 21210227 in words is "twenty-one million, two hundred ten thousand, two hundred twenty-seven".