21210041 has 2 divisors, whose sum is σ = 21210042. Its totient is φ = 21210040.

The previous prime is 21210037. The next prime is 21210053. The reversal of 21210041 is 14001212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21196816 + 13225 = 4604^2 + 115^2 .

It is a cyclic number.

It is not a de Polignac number, because 21210041 - 2² = 21210037 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21210011) 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, 10605020 + 10605021.

It is an arithmetic number, because the mean of its divisors is an integer number (10605021).

Almost surely, 2^21210041 is an apocalyptic number.

It is an amenable number.

21210041 is a deficient number, since it is larger than the sum of its proper divisors (1).

21210041 is an equidigital number, since it uses as much as digits as its factorization.

21210041 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 21210041 is about 4605.4360271314. The cubic root of 21210041 is about 276.8091888384.

Adding to 21210041 its reverse (14001212), we get a palindrome (35211253).

The spelling of 21210041 in words is "twenty-one million, two hundred ten thousand, forty-one".