405491605 has 8 divisors (see below), whose sum is σ = 495771192. Its totient is φ = 318272448.

The previous prime is 405491561. The next prime is 405491627. The reversal of 405491605 is 506194504.

It can be written as a sum of positive squares in 4 ways, for example, as 22193521 + 383298084 = 4711^2 + 19578^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 405491605 - 2⁷ = 405491477 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 764814 + ... + 765343.

It is an arithmetic number, because the mean of its divisors is an integer number (61971399).

Almost surely, 2^405491605 is an apocalyptic number.

It is an amenable number.

405491605 is a deficient number, since it is larger than the sum of its proper divisors (90279587).

405491605 is a wasteful number, since it uses less digits than its factorization.

405491605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1530215.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 405491605 is about 20136.8221177027. The cubic root of 405491605 is about 740.1628598210.

It can be divided in two parts, 4054 and 91605, that added together give a palindrome (95659).

The spelling of 405491605 in words is "four hundred five million, four hundred ninety-one thousand, six hundred five".