21211220227 has 2 divisors, whose sum is σ = 21211220228. Its totient is φ = 21211220226.

The previous prime is 21211220183. The next prime is 21211220237. The reversal of 21211220227 is 72202211212.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21211220227 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21211220198 and 21211220207.

It is not a weakly prime, because it can be changed into another prime (21211220237) 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 as a sum of consecutive naturals, namely, 10605610113 + 10605610114.

It is an arithmetic number, because the mean of its divisors is an integer number (10605610114).

Almost surely, 2^21211220227 is an apocalyptic number.

21211220227 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211220227 is an equidigital number, since it uses as much as digits as its factorization.

21211220227 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.

Adding to 21211220227 its reverse (72202211212), we get a palindrome (93413431439).

The spelling of 21211220227 in words is "twenty-one billion, two hundred eleven million, two hundred twenty thousand, two hundred twenty-seven".