21033413 has 2 divisors, whose sum is σ = 21033414. Its totient is φ = 21033412.

The previous prime is 21033401. The next prime is 21033433. The reversal of 21033413 is 31433012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17581249 + 3452164 = 4193^2 + 1858^2 .

It is a cyclic number.

It is not a de Polignac number, because 21033413 - 2¹⁸ = 20771269 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21033391 and 21033400.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21033433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516706 + 10516707.

It is an arithmetic number, because the mean of its divisors is an integer number (10516707).

Almost surely, 2^21033413 is an apocalyptic number.

It is an amenable number.

21033413 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033413 is an equidigital number, since it uses as much as digits as its factorization.

21033413 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 21033413 is about 4586.2199031446. The cubic root of 21033413 is about 276.0386638056.

Adding to 21033413 its reverse (31433012), we get a palindrome (52466425).

The spelling of 21033413 in words is "twenty-one million, thirty-three thousand, four hundred thirteen".