561605305 has 4 divisors (see below), whose sum is σ = 673926372. Its totient is φ = 449284240.

The previous prime is 561605227. The next prime is 561605321. The reversal of 561605305 is 503506165.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 503506165 = 5 ⋅100701233.

It can be written as a sum of positive squares in 2 ways, for example, as 334560681 + 227044624 = 18291^2 + 15068^2 .

It is a de Polignac number, because none of the positive numbers 2^k-561605305 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56160526 + ... + 56160535.

It is an arithmetic number, because the mean of its divisors is an integer number (168481593).

Almost surely, 2^561605305 is an apocalyptic number.

It is an amenable number.

561605305 is a deficient number, since it is larger than the sum of its proper divisors (112321067).

561605305 is a wasteful number, since it uses less digits than its factorization.

561605305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112321066.

The product of its (nonzero) digits is 13500, while the sum is 31.

The square root of 561605305 is about 23698.2131182923. The cubic root of 561605305 is about 825.0439180783.

The spelling of 561605305 in words is "five hundred sixty-one million, six hundred five thousand, three hundred five".