21241873 has 2 divisors, whose sum is σ = 21241874. Its totient is φ = 21241872.

The previous prime is 21241861. The next prime is 21241877. The reversal of 21241873 is 37814212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21224449 + 17424 = 4607^2 + 132^2 .

It is a cyclic number.

It is not a de Polignac number, because 21241873 - 2⁹ = 21241361 is a prime.

It is not a weakly prime, because it can be changed into another prime (21241877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10620936 + 10620937.

It is an arithmetic number, because the mean of its divisors is an integer number (10620937).

Almost surely, 2^21241873 is an apocalyptic number.

It is an amenable number.

21241873 is a deficient number, since it is larger than the sum of its proper divisors (1).

21241873 is an equidigital number, since it uses as much as digits as its factorization.

21241873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2688, while the sum is 28.

The square root of 21241873 is about 4608.8906474335. The cubic root of 21241873 is about 276.9475979019.

The spelling of 21241873 in words is "twenty-one million, two hundred forty-one thousand, eight hundred seventy-three".