821829 has 4 divisors (see below), whose sum is σ = 1095776. Its totient is φ = 547884.

The previous prime is 821827. The next prime is 821833. The reversal of 821829 is 928128.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 821829 - 2¹ = 821827 is a prime.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 821796 and 821805.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 821829.

It is not an unprimeable number, because it can be changed into a prime (821827) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136969 + ... + 136974.

It is an arithmetic number, because the mean of its divisors is an integer number (273944).

2⁸²¹⁸²⁹ is an apocalyptic number.

It is an amenable number.

821829 is a deficient number, since it is larger than the sum of its proper divisors (273947).

821829 is a wasteful number, since it uses less digits than its factorization.

821829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273946.

The product of its digits is 2304, while the sum is 30.

The square root of 821829 is about 906.5478476065. The cubic root of 821829 is about 93.6685550433.

The spelling of 821829 in words is "eight hundred twenty-one thousand, eight hundred twenty-nine".