400855 has 16 divisors (see below), whose sum is σ = 592704. Its totient is φ = 253440.

The previous prime is 400853. The next prime is 400859. The reversal of 400855 is 558004.

It is a happy number.

It is not a de Polignac number, because 400855 - 2¹ = 400853 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400853) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15 + ... + 895.

It is an arithmetic number, because the mean of its divisors is an integer number (37044).

2⁴⁰⁰⁸⁵⁵ is an apocalyptic number.

400855 is a deficient number, since it is larger than the sum of its proper divisors (191849).

400855 is a wasteful number, since it uses less digits than its factorization.

400855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 906.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 400855 is about 633.1311080653. The cubic root of 400855 is about 73.7330900616.

Adding to 400855 its reverse (558004), we get a palindrome (958859).

The spelling of 400855 in words is "four hundred thousand, eight hundred fifty-five".