400543400 has 48 divisors (see below), whose sum is σ = 951099840. Its totient is φ = 156804800.

The previous prime is 400543399. The next prime is 400543411. The reversal of 400543400 is 4345004.

It is a happy number.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11906 + ... + 30705.

It is an arithmetic number, because the mean of its divisors is an integer number (19814580).

Almost surely, 2^400543400 is an apocalyptic number.

400543400 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400543400 is an abundant number, since it is smaller than the sum of its proper divisors (550556440).

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

400543400 is a wasteful number, since it uses less digits than its factorization.

400543400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42674 (or 42665 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 20.

The square root of 400543400 is about 20013.5803893256. The cubic root of 400543400 is about 737.1397992067.

Adding to 400543400 its reverse (4345004), we get a palindrome (404888404).

The spelling of 400543400 in words is "four hundred million, five hundred forty-three thousand, four hundred".