820040000 has 280 divisors, whose sum is σ = 2332878240. Its totient is φ = 283392000.

The previous prime is 820039967. The next prime is 820040017. The reversal of 820040000 is 40028.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 9879959 + ... + 9880041.

It is an arithmetic number, because the mean of its divisors is an integer number (8331708).

Almost surely, 2^820040000 is an apocalyptic number.

820040000 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 820040000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1166439120).

820040000 is an abundant number, since it is smaller than the sum of its proper divisors (1512838240).

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

820040000 is a wasteful number, since it uses less digits than its factorization.

820040000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 820040000 is about 28636.3405483312. The cubic root of 820040000 is about 936.0053814189.

Adding to 820040000 its reverse (40028), we get a palindrome (820080028).

The spelling of 820040000 in words is "eight hundred twenty million, forty thousand".