405664605 has 80 divisors (see below), whose sum is σ = 762009600. Its totient is φ = 206219520.

The previous prime is 405664603. The next prime is 405664627. The reversal of 405664605 is 506466504.

It is a happy number.

405664605 is a `hidden beast` number, since 4 + 0 + 5 + 6 + 646 + 0 + 5 = 666.

It is not a de Polignac number, because 405664605 - 2¹ = 405664603 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 405664605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405664603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 991641 + ... + 992049.

It is an arithmetic number, because the mean of its divisors is an integer number (9525120).

Almost surely, 2^405664605 is an apocalyptic number.

405664605 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

405664605 is a deficient number, since it is larger than the sum of its proper divisors (356344995).

405664605 is a wasteful number, since it uses less digits than its factorization.

405664605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536 (or 527 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 405664605 is about 20141.1172728824. The cubic root of 405664605 is about 740.2681065283.

The spelling of 405664605 in words is "four hundred five million, six hundred sixty-four thousand, six hundred five".