21500833 has 2 divisors, whose sum is σ = 21500834. Its totient is φ = 21500832.

The previous prime is 21500827. The next prime is 21500893. The reversal of 21500833 is 33800512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19289664 + 2211169 = 4392^2 + 1487^2 .

It is a cyclic number.

It is not a de Polignac number, because 21500833 - 2⁹ = 21500321 is a prime.

It is not a weakly prime, because it can be changed into another prime (21500813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10750416 + 10750417.

It is an arithmetic number, because the mean of its divisors is an integer number (10750417).

Almost surely, 2^21500833 is an apocalyptic number.

It is an amenable number.

21500833 is a deficient number, since it is larger than the sum of its proper divisors (1).

21500833 is an equidigital number, since it uses as much as digits as its factorization.

21500833 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 21500833 is about 4636.8990715779. The cubic root of 21500833 is about 278.0684794123.

The spelling of 21500833 in words is "twenty-one million, five hundred thousand, eight hundred thirty-three".