821343760 has 80 divisors (see below), whose sum is σ = 2024727552. Its totient is φ = 309312000.

The previous prime is 821343751. The next prime is 821343811. The reversal of 821343760 is 67343128.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87285 + ... + 96235.

Almost surely, 2^821343760 is an apocalyptic number.

821343760 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 821343760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1012363776).

821343760 is an abundant number, since it is smaller than the sum of its proper divisors (1203383792).

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

821343760 is a wasteful number, since it uses less digits than its factorization.

821343760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9032 (or 9026 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 34.

The square root of 821343760 is about 28659.0955893587. The cubic root of 821343760 is about 936.5011622040.

Adding to 821343760 its reverse (67343128), we get a palindrome (888686888).

The spelling of 821343760 in words is "eight hundred twenty-one million, three hundred forty-three thousand, seven hundred sixty".