20281211 has 2 divisors, whose sum is σ = 20281212. Its totient is φ = 20281210.

The previous prime is 20281199. The next prime is 20281229. The reversal of 20281211 is 11218202.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20281211 - 2¹⁰ = 20280187 is a prime.

It is a super-2 number, since 2×20281211² = 822655039253042, which contains 22 as substring.

It is a Chen prime.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 20281211.

It is not a weakly prime, because it can be changed into another prime (20281241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10140605 + 10140606.

It is an arithmetic number, because the mean of its divisors is an integer number (10140606).

Almost surely, 2^20281211 is an apocalyptic number.

20281211 is a deficient number, since it is larger than the sum of its proper divisors (1).

20281211 is an equidigital number, since it uses as much as digits as its factorization.

20281211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 17.

The square root of 20281211 is about 4503.4665536673. The cubic root of 20281211 is about 272.7080519821.

Adding to 20281211 its reverse (11218202), we get a palindrome (31499413).

The spelling of 20281211 in words is "twenty million, two hundred eighty-one thousand, two hundred eleven".