605005661 has 4 divisors (see below), whose sum is σ = 651544572. Its totient is φ = 558466752.

The previous prime is 605005651. The next prime is 605005663. The reversal of 605005661 is 166500506.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 99880036 + 505125625 = 9994^2 + 22475^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-605005661 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 (605005663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23269436 + ... + 23269461.

It is an arithmetic number, because the mean of its divisors is an integer number (162886143).

Almost surely, 2^605005661 is an apocalyptic number.

It is an amenable number.

605005661 is a deficient number, since it is larger than the sum of its proper divisors (46538911).

605005661 is a wasteful number, since it uses less digits than its factorization.

605005661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46538910.

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 605005661 is about 24596.8628284178. The cubic root of 605005661 is about 845.7716937639.

The spelling of 605005661 in words is "six hundred five million, five thousand, six hundred sixty-one".