400105 has 4 divisors (see below), whose sum is σ = 480132. Its totient is φ = 320080.

The previous prime is 400093. The next prime is 400109. The reversal of 400105 is 501004.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 59049 + 341056 = 243^2 + 584^2 .

It is a de Polignac number, because none of the positive numbers 2^k-400105 is a prime.

It is a super-2 number, since 2×400105² = 320168022050, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

400105 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 400091 and 400100.

It is not an unprimeable number, because it can be changed into a prime (400109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40006 + ... + 40015.

It is an arithmetic number, because the mean of its divisors is an integer number (120033).

2⁴⁰⁰¹⁰⁵ is an apocalyptic number.

It is an amenable number.

400105 is a deficient number, since it is larger than the sum of its proper divisors (80027).

400105 is an equidigital number, since it uses as much as digits as its factorization.

400105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80026.

The product of its (nonzero) digits is 20, while the sum is 10.

The square root of 400105 is about 632.5385363755. The cubic root of 400105 is about 73.6870764639.

Adding to 400105 its reverse (501004), we get a palindrome (901109).

It can be divided in two parts, 400 and 105, that added together give a palindrome (505).

The spelling of 400105 in words is "four hundred thousand, one hundred five".