21133009 has 2 divisors, whose sum is σ = 21133010. Its totient is φ = 21133008.

The previous prime is 21133003. The next prime is 21133027. The reversal of 21133009 is 90033112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19998784 + 1134225 = 4472^2 + 1065^2 .

It is a cyclic number.

It is not a de Polignac number, because 21133009 - 2⁹ = 21132497 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21133003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10566504 + 10566505.

It is an arithmetic number, because the mean of its divisors is an integer number (10566505).

Almost surely, 2^21133009 is an apocalyptic number.

It is an amenable number.

21133009 is a deficient number, since it is larger than the sum of its proper divisors (1).

21133009 is an equidigital number, since it uses as much as digits as its factorization.

21133009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 19.

The square root of 21133009 is about 4597.0652594889. The cubic root of 21133009 is about 276.4736711477.

The spelling of 21133009 in words is "twenty-one million, one hundred thirty-three thousand, nine".