21068441 has 2 divisors, whose sum is σ = 21068442. Its totient is φ = 21068440.

The previous prime is 21068417. The next prime is 21068477. The reversal of 21068441 is 14486012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18524416 + 2544025 = 4304^2 + 1595^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21068441 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21068441.

It is not a weakly prime, because it can be changed into another prime (21068041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10534220 + 10534221.

It is an arithmetic number, because the mean of its divisors is an integer number (10534221).

Almost surely, 2^21068441 is an apocalyptic number.

It is an amenable number.

21068441 is a deficient number, since it is larger than the sum of its proper divisors (1).

21068441 is an equidigital number, since it uses as much as digits as its factorization.

21068441 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 21068441 is about 4590.0371458192. The cubic root of 21068441 is about 276.1918125093.

The spelling of 21068441 in words is "twenty-one million, sixty-eight thousand, four hundred forty-one".