10405 has 4 divisors (see below), whose sum is σ = 12492. Its totient is φ = 8320.

The previous prime is 10399. The next prime is 10427. The reversal of 10405 is 50401.

10405 = T₆₂ + T₆₃ + ... + T₆₆.

It is a Cunningham number, because it is equal to 102²+1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50401 = 13 ⋅3877.

It can be written as a sum of positive squares in 2 ways, for example, as 3844 + 6561 = 62^2 + 81^2 .

It is not a de Polignac number, because 10405 - 2¹³ = 2213 is a prime.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 10391 and 10400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1036 + ... + 1045.

It is an arithmetic number, because the mean of its divisors is an integer number (3123).

2¹⁰⁴⁰⁵ is an apocalyptic number.

It is an amenable number.

10405 is a deficient number, since it is larger than the sum of its proper divisors (2087).

10405 is an equidigital number, since it uses as much as digits as its factorization.

10405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2086.

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

The square root of 10405 is about 102.0049018430. The cubic root of 10405 is about 21.8313551549.

Adding to 10405 its reverse (50401), we get a palindrome (60806).

The spelling of 10405 in words is "ten thousand, four hundred five".