21703229 has 2 divisors, whose sum is σ = 21703230. Its totient is φ = 21703228.

The previous prime is 21703211. The next prime is 21703247. The reversal of 21703229 is 92230712.

It is a balanced prime because it is at equal distance from previous prime (21703211) and next prime (21703247).

It can be written as a sum of positive squares in only one way, i.e., 19377604 + 2325625 = 4402^2 + 1525^2 .

It is a cyclic number.

It is not a de Polignac number, because 21703229 - 2²⁴ = 4926013 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21703198 and 21703207.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21703729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10851614 + 10851615.

It is an arithmetic number, because the mean of its divisors is an integer number (10851615).

Almost surely, 2^21703229 is an apocalyptic number.

It is an amenable number.

21703229 is a deficient number, since it is larger than the sum of its proper divisors (1).

21703229 is an equidigital number, since it uses as much as digits as its factorization.

21703229 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 21703229 is about 4658.6724503876. The cubic root of 21703229 is about 278.9382793632.

The spelling of 21703229 in words is "twenty-one million, seven hundred three thousand, two hundred twenty-nine".