821430 has 24 divisors (see below), whose sum is σ = 2135952. Its totient is φ = 219024.

The previous prime is 821411. The next prime is 821441. The reversal of 821430 is 34128.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4474 + ... + 4653.

It is an arithmetic number, because the mean of its divisors is an integer number (88998).

2⁸²¹⁴³⁰ is an apocalyptic number.

821430 is an abundant number, since it is smaller than the sum of its proper divisors (1314522).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

821430 is a wasteful number, since it uses less digits than its factorization.

821430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9140 (or 9137 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 821430 is about 906.3277552850. The cubic root of 821430 is about 93.6533938181.

Adding to 821430 its reverse (34128), we get a palindrome (855558).

The spelling of 821430 in words is "eight hundred twenty-one thousand, four hundred thirty".