400243400 has 48 divisors (see below), whose sum is σ = 935477700. Its totient is φ = 159252480.

The previous prime is 400243373. The next prime is 400243457. The reversal of 400243400 is 4342004.

It can be written as a sum of positive squares in 6 ways, for example, as 21473956 + 378769444 = 4634^2 + 19462^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33416 + ... + 43784.

Almost surely, 2^400243400 is an apocalyptic number.

400243400 is a gapful number since it is divisible by the number (40) 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 400243400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (467738850).

400243400 is an abundant number, since it is smaller than the sum of its proper divisors (535234300).

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

400243400 is a wasteful number, since it uses less digits than its factorization.

400243400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10578 (or 10569 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 17.

The square root of 400243400 is about 20006.0840746009. The cubic root of 400243400 is about 736.9557183029.

Adding to 400243400 its reverse (4342004), we get a palindrome (404585404).

The spelling of 400243400 in words is "four hundred million, two hundred forty-three thousand, four hundred".