400800800 has 36 divisors (see below), whose sum is σ = 978456906. Its totient is φ = 160320000.

The previous prime is 400800773. The next prime is 400800817. The reversal of 400800800 is 8008004.

It can be written as a sum of positive squares in 3 ways, for example, as 144672784 + 256128016 = 12028^2 + 16004^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 249701 + ... + 251300.

Almost surely, 2^400800800 is an apocalyptic number.

400800800 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400800800 is an abundant number, since it is smaller than the sum of its proper divisors (577656106).

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

400800800 is a wasteful number, since it uses less digits than its factorization.

400800800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501021 (or 501008 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 400800800 is about 20020.0099900075. The cubic root of 400800800 is about 737.2976673718.

Adding to 400800800 its reverse (8008004), we get a palindrome (408808804).

The spelling of 400800800 in words is "four hundred million, eight hundred thousand, eight hundred".