21010229 has 2 divisors, whose sum is σ = 21010230. Its totient is φ = 21010228.

The previous prime is 21010217. The next prime is 21010237. The reversal of 21010229 is 92201012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19624900 + 1385329 = 4430^2 + 1177^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010229 - 2⁸ = 21009973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21010259) 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, 10505114 + 10505115.

It is an arithmetic number, because the mean of its divisors is an integer number (10505115).

Almost surely, 2^21010229 is an apocalyptic number.

It is an amenable number.

21010229 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010229 is an equidigital number, since it uses as much as digits as its factorization.

21010229 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 21010229 is about 4583.6916344798. The cubic root of 21010229 is about 275.9372056612.

The spelling of 21010229 in words is "twenty-one million, ten thousand, two hundred twenty-nine".