405440805 has 32 divisors (see below), whose sum is σ = 808777728. Its totient is φ = 168494400.

The previous prime is 405440779. The next prime is 405440813. The reversal of 405440805 is 508044504.

It is not a de Polignac number, because 405440805 - 2⁵ = 405440773 is a prime.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 174361 + ... + 176670.

It is an arithmetic number, because the mean of its divisors is an integer number (25274304).

Almost surely, 2^405440805 is an apocalyptic number.

It is an amenable number.

405440805 is a deficient number, since it is larger than the sum of its proper divisors (403336923).

405440805 is a wasteful number, since it uses less digits than its factorization.

405440805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351057.

The product of its (nonzero) digits is 12800, while the sum is 30.

The square root of 405440805 is about 20135.5607073655. The cubic root of 405440805 is about 740.1319493220.

The spelling of 405440805 in words is "four hundred five million, four hundred forty thousand, eight hundred five".