821360 has 20 divisors (see below), whose sum is σ = 1909848. Its totient is φ = 328512.

The previous prime is 821333. The next prime is 821377. The reversal of 821360 is 63128.

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a nialpdrome in base 11 and base 16.

It is a congruent number.

It is an unprimeable number.

821360 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5054 + ... + 5213.

2⁸²¹³⁶⁰ is an apocalyptic number.

821360 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

821360 is an abundant number, since it is smaller than the sum of its proper divisors (1088488).

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

821360 is a wasteful number, since it uses less digits than its factorization.

821360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10280 (or 10274 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 821360 is about 906.2891370860. The cubic root of 821360 is about 93.6507334479.

Adding to 821360 its reverse (63128), we get a palindrome (884488).

The spelling of 821360 in words is "eight hundred twenty-one thousand, three hundred sixty".