405826 has 8 divisors (see below), whose sum is σ = 629820. Its totient is φ = 195888.

The previous prime is 405817. The next prime is 405827. The reversal of 405826 is 628504.

405826 = 104² + 105² + ... + 132².

It can be written as a sum of positive squares in 2 ways, for example, as 403225 + 2601 = 635^2 + 51^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 405826.

It is not an unprimeable number, because it can be changed into a prime (405827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3441 + ... + 3556.

2⁴⁰⁵⁸²⁶ is an apocalyptic number.

405826 is a deficient number, since it is larger than the sum of its proper divisors (223994).

405826 is a wasteful number, since it uses less digits than its factorization.

405826 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7028.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 405826 is about 637.0447394022. The cubic root of 405826 is about 74.0366266214.

The spelling of 405826 in words is "four hundred five thousand, eight hundred twenty-six".