1660885405 has 8 divisors (see below), whose sum is σ = 1994316984. Its totient is φ = 1327872000.

The previous prime is 1660885381. The next prime is 1660885409. The reversal of 1660885405 is 5045880661.

It can be written as a sum of positive squares in 4 ways, for example, as 401842116 + 1259043289 = 20046^2 + 35483^2 .

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

It is not a de Polignac number, because 1660885405 - 2⁹ = 1660884893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1660885409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95736 + ... + 111745.

It is an arithmetic number, because the mean of its divisors is an integer number (249289623).

Almost surely, 2^1660885405 is an apocalyptic number.

It is an amenable number.

1660885405 is a deficient number, since it is larger than the sum of its proper divisors (333431579).

1660885405 is a wasteful number, since it uses less digits than its factorization.

1660885405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209087.

The product of its (nonzero) digits is 230400, while the sum is 43.

The square root of 1660885405 is about 40753.9618319495. The cubic root of 1660885405 is about 1184.2586246141.

The spelling of 1660885405 in words is "one billion, six hundred sixty million, eight hundred eighty-five thousand, four hundred five".