400544400 has 60 divisors (see below), whose sum is σ = 1283081072. Its totient is φ = 106811520.

The previous prime is 400544393. The next prime is 400544401. The reversal of 400544400 is 4445004.

It is a tau number, because it is divible by the number of its divisors (60).

It is not an unprimeable number, because it can be changed into a prime (400544401) by changing a digit.

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, 165694 + ... + 168093.

Almost surely, 2^400544400 is an apocalyptic number.

400544400 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400544400 is an abundant number, since it is smaller than the sum of its proper divisors (882536672).

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

400544400 is a wasteful number, since it uses less digits than its factorization.

400544400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333808 (or 333797 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 21.

The square root of 400544400 is about 20013.6053723461. The cubic root of 400544400 is about 737.1404126560.

Adding to 400544400 its reverse (4445004), we get a palindrome (404989404).

The spelling of 400544400 in words is "four hundred million, five hundred forty-four thousand, four hundred".