21084227 has 2 divisors, whose sum is σ = 21084228. Its totient is φ = 21084226.

The previous prime is 21084187. The next prime is 21084253. The reversal of 21084227 is 72248012.

It is an a-pointer prime, because the next prime (21084253) can be obtained adding 21084227 to its sum of digits (26).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21084227 - 2¹⁴ = 21067843 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21084196 and 21084205.

It is not a weakly prime, because it can be changed into another prime (21084257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10542113 + 10542114.

It is an arithmetic number, because the mean of its divisors is an integer number (10542114).

Almost surely, 2^21084227 is an apocalyptic number.

21084227 is a deficient number, since it is larger than the sum of its proper divisors (1).

21084227 is an equidigital number, since it uses as much as digits as its factorization.

21084227 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 21084227 is about 4591.7564177556. The cubic root of 21084227 is about 276.2607762495.

The spelling of 21084227 in words is "twenty-one million, eighty-four thousand, two hundred twenty-seven".