21826829 has 2 divisors, whose sum is σ = 21826830. Its totient is φ = 21826828.

The previous prime is 21826817. The next prime is 21826859. The reversal of 21826829 is 92862812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19377604 + 2449225 = 4402^2 + 1565^2 .

It is a cyclic number.

It is not a de Polignac number, because 21826829 - 2¹² = 21822733 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21826792 and 21826801.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21826859) 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, 10913414 + 10913415.

It is an arithmetic number, because the mean of its divisors is an integer number (10913415).

Almost surely, 2^21826829 is an apocalyptic number.

It is an amenable number.

21826829 is a deficient number, since it is larger than the sum of its proper divisors (1).

21826829 is an equidigital number, since it uses as much as digits as its factorization.

21826829 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 38.

The square root of 21826829 is about 4671.9191987876. The cubic root of 21826829 is about 279.4667956369.

The spelling of 21826829 in words is "twenty-one million, eight hundred twenty-six thousand, eight hundred twenty-nine".