400845 has 8 divisors (see below), whose sum is σ = 641376. Its totient is φ = 213776.

The previous prime is 400837. The next prime is 400849. The reversal of 400845 is 548004.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 400845 - 2³ = 400837 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13347 + ... + 13376.

It is an arithmetic number, because the mean of its divisors is an integer number (80172).

2⁴⁰⁰⁸⁴⁵ is an apocalyptic number.

It is an amenable number.

400845 is a deficient number, since it is larger than the sum of its proper divisors (240531).

400845 is a wasteful number, since it uses less digits than its factorization.

400845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26731.

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 400845 is about 633.1232107576. The cubic root of 400845 is about 73.7324769246.

Adding to 400845 its reverse (548004), we get a palindrome (948849).

The spelling of 400845 in words is "four hundred thousand, eight hundred forty-five".