821023 has 8 divisors (see below), whose sum is σ = 956448. Its totient is φ = 690144.

The previous prime is 821003. The next prime is 821027. The reversal of 821023 is 320128.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 821023 - 2⁵ = 820991 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 820988 and 821006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821027) 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 in 7 ways as a sum of consecutive naturals, for example, 736 + ... + 1477.

It is an arithmetic number, because the mean of its divisors is an integer number (119556).

2⁸²¹⁰²³ is an apocalyptic number.

821023 is a deficient number, since it is larger than the sum of its proper divisors (135425).

821023 is a wasteful number, since it uses less digits than its factorization.

821023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2273.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 821023 is about 906.1031950060. The cubic root of 821023 is about 93.6379235495.

The spelling of 821023 in words is "eight hundred twenty-one thousand, twenty-three".