21122611 has 2 divisors, whose sum is σ = 21122612. Its totient is φ = 21122610.

The previous prime is 21122603. The next prime is 21122641. The reversal of 21122611 is 11622112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21122611 - 2³ = 21122603 is a prime.

It is not a weakly prime, because it can be changed into another prime (21122641) 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, 10561305 + 10561306.

It is an arithmetic number, because the mean of its divisors is an integer number (10561306).

Almost surely, 2^21122611 is an apocalyptic number.

21122611 is a deficient number, since it is larger than the sum of its proper divisors (1).

21122611 is an equidigital number, since it uses as much as digits as its factorization.

21122611 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48, while the sum is 16.

The square root of 21122611 is about 4595.9341814260. The cubic root of 21122611 is about 276.4283195865.

Adding to 21122611 its reverse (11622112), we get a palindrome (32744723).

It can be divided in two parts, 211 and 22611, that added together give a palindrome (22822).

The spelling of 21122611 in words is "twenty-one million, one hundred twenty-two thousand, six hundred eleven".