21800227 has 2 divisors, whose sum is σ = 21800228. Its totient is φ = 21800226.

The previous prime is 21800197. The next prime is 21800237. The reversal of 21800227 is 72200812.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21800227 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21800198 and 21800207.

It is not a weakly prime, because it can be changed into another prime (21800237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10900113 + 10900114.

It is an arithmetic number, because the mean of its divisors is an integer number (10900114).

Almost surely, 2^21800227 is an apocalyptic number.

21800227 is a deficient number, since it is larger than the sum of its proper divisors (1).

21800227 is an equidigital number, since it uses as much as digits as its factorization.

21800227 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 21800227 is about 4669.0713209374. The cubic root of 21800227 is about 279.3532137385.

The spelling of 21800227 in words is "twenty-one million, eight hundred thousand, two hundred twenty-seven".