605121660 has 144 divisors (see below), whose sum is σ = 2156525280. Its totient is φ = 135406080.

The previous prime is 605121659. The next prime is 605121683. The reversal of 605121660 is 66121506.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13986 + ... + 37494.

It is an arithmetic number, because the mean of its divisors is an integer number (14975870).

Almost surely, 2^605121660 is an apocalyptic number.

605121660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 605121660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1078262640).

605121660 is an abundant number, since it is smaller than the sum of its proper divisors (1551403620).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

605121660 is a wasteful number, since it uses less digits than its factorization.

605121660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23548 (or 23543 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 605121660 is about 24599.2207193643. The cubic root of 605121660 is about 845.8257441679.

It can be divided in two parts, 605 and 121660, that added together give a triangular number (122265 = T₄₉₄).

The spelling of 605121660 in words is "six hundred five million, one hundred twenty-one thousand, six hundred sixty".