400812 has 24 divisors (see below), whose sum is σ = 946176. Its totient is φ = 132048.

The previous prime is 400759. The next prime is 400823. The reversal of 400812 is 218004.

It is a junction number, because it is equal to n+sod(n) for n = 400791 and 400800.

It is an unprimeable number.

400812 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1393 + ... + 1655.

It is an arithmetic number, because the mean of its divisors is an integer number (39424).

2⁴⁰⁰⁸¹² is an apocalyptic number.

It is an amenable number.

400812 is an abundant number, since it is smaller than the sum of its proper divisors (545364).

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

400812 is a wasteful number, since it uses less digits than its factorization.

400812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397 (or 395 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 400812 is about 633.0971489432. The cubic root of 400812 is about 73.7304535004.

Adding to 400812 its reverse (218004), we get a palindrome (618816).

The spelling of 400812 in words is "four hundred thousand, eight hundred twelve".