21244073 has 2 divisors, whose sum is σ = 21244074. Its totient is φ = 21244072.

The previous prime is 21244063. The next prime is 21244121. The reversal of 21244073 is 37044212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21086464 + 157609 = 4592^2 + 397^2 .

It is a cyclic number.

It is not a de Polignac number, because 21244073 - 2¹⁰ = 21243049 is a prime.

It is not a weakly prime, because it can be changed into another prime (21244063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10622036 + 10622037.

It is an arithmetic number, because the mean of its divisors is an integer number (10622037).

Almost surely, 2^21244073 is an apocalyptic number.

It is an amenable number.

21244073 is a deficient number, since it is larger than the sum of its proper divisors (1).

21244073 is an equidigital number, since it uses as much as digits as its factorization.

21244073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 21244073 is about 4609.1293104013. The cubic root of 21244073 is about 276.9571586357.

Adding to 21244073 its reverse (37044212), we get a palindrome (58288285).

The spelling of 21244073 in words is "twenty-one million, two hundred forty-four thousand, seventy-three".