823540400 has 30 divisors (see below), whose sum is σ = 1978556772. Its totient is φ = 329416000.

The previous prime is 823540397. The next prime is 823540409. The reversal of 823540400 is 4045328.

It is a self number, because there is not a number n which added to its sum of digits gives 823540400.

It is not an unprimeable number, because it can be changed into a prime (823540409) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 1029026 + ... + 1029825.

Almost surely, 2^823540400 is an apocalyptic number.

823540400 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

823540400 is an abundant number, since it is smaller than the sum of its proper divisors (1155016372).

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

823540400 is a wasteful number, since it uses less digits than its factorization.

823540400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2058869 (or 2058858 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 823540400 is about 28697.3936098734. The cubic root of 823540400 is about 937.3352931389.

Adding to 823540400 its reverse (4045328), we get a palindrome (827585728).

The spelling of 823540400 in words is "eight hundred twenty-three million, five hundred forty thousand, four hundred".