400900 has 36 divisors (see below), whose sum is σ = 920080. Its totient is φ = 151200.

The previous prime is 400871. The next prime is 400903. The reversal of 400900 is 9004.

It is a happy number.

400900 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

400900 is a modest number, since divided by 900 gives 400 as remainder.

It is not an unprimeable number, because it can be changed into a prime (400903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1795 + ... + 2005.

2⁴⁰⁰⁹⁰⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (460040).

400900 is an abundant number, since it is smaller than the sum of its proper divisors (519180).

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

400900 is a wasteful number, since it uses less digits than its factorization.

400900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244 (or 237 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 400900 is about 633.1666447311. The cubic root of 400900 is about 73.7358490517.

Adding to 400900 its reverse (9004), we get a palindrome (409904).

It can be divided in two parts, 400 and 900, that multiplied together give a square (360000 = 600²).

The spelling of 400900 in words is "four hundred thousand, nine hundred".