400431400 has 24 divisors (see below), whose sum is σ = 931003470. Its totient is φ = 160172480.

The previous prime is 400431397. The next prime is 400431401. The reversal of 400431400 is 4134004.

It can be written as a sum of positive squares in 3 ways, for example, as 381889764 + 18541636 = 19542^2 + 4306^2 .

It is a super-3 number, since 3×400431400³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (400431401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1000879 + ... + 1001278.

Almost surely, 2^400431400 is an apocalyptic number.

400431400 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400431400 is an abundant number, since it is smaller than the sum of its proper divisors (530572070).

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

400431400 is a wasteful number, since it uses less digits than its factorization.

400431400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2002173 (or 2002164 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 400431400 is about 20010.7820936614. The cubic root of 400431400 is about 737.0710864248.

Adding to 400431400 its reverse (4134004), we get a palindrome (404565404).

The spelling of 400431400 in words is "four hundred million, four hundred thirty-one thousand, four hundred".