20820829 has 2 divisors, whose sum is σ = 20820830. Its totient is φ = 20820828.

The previous prime is 20820817. The next prime is 20820851. The reversal of 20820829 is 92802802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18292729 + 2528100 = 4277^2 + 1590^2 .

It is a cyclic number.

It is not a de Polignac number, because 20820829 - 2⁵ = 20820797 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20820829.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20820889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10410414 + 10410415.

It is an arithmetic number, because the mean of its divisors is an integer number (10410415).

Almost surely, 2^20820829 is an apocalyptic number.

It is an amenable number.

20820829 is a deficient number, since it is larger than the sum of its proper divisors (1).

20820829 is an equidigital number, since it uses as much as digits as its factorization.

20820829 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 20820829 is about 4562.9846591896. The cubic root of 20820829 is about 275.1055418582.

The spelling of 20820829 in words is "twenty million, eight hundred twenty thousand, eight hundred twenty-nine".