824640 has 56 divisors (see below), whose sum is σ = 2621280. Its totient is φ = 219648.

The previous prime is 824609. The next prime is 824641. The reversal of 824640 is 46428.

It is a super-2 number, since 2×824640² = 1360062259200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 824640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (824641) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 531 + ... + 1389.

2⁸²⁴⁶⁴⁰ is an apocalyptic number.

824640 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 824640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1310640).

824640 is an abundant number, since it is smaller than the sum of its proper divisors (1796640).

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

824640 is a wasteful number, since it uses less digits than its factorization.

824640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 879 (or 869 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 824640 is about 908.0969111279. The cubic root of 824640 is about 93.7752287657.

The spelling of 824640 in words is "eight hundred twenty-four thousand, six hundred forty".