820429 has 2 divisors, whose sum is σ = 820430. Its totient is φ = 820428.

The previous prime is 820427. The next prime is 820441. The reversal of 820429 is 924028.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 592900 + 227529 = 770^2 + 477^2 .

It is a cyclic number.

It is not a de Polignac number, because 820429 - 2¹ = 820427 is a prime.

Together with 820427, it forms a pair of twin primes.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410214 + 410215.

It is an arithmetic number, because the mean of its divisors is an integer number (410215).

2⁸²⁰⁴²⁹ is an apocalyptic number.

It is an amenable number.

820429 is a deficient number, since it is larger than the sum of its proper divisors (1).

820429 is an equidigital number, since it uses as much as digits as its factorization.

820429 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 820429 is about 905.7753584637. The cubic root of 820429 is about 93.6153361410.

The spelling of 820429 in words is "eight hundred twenty thousand, four hundred twenty-nine".