561745 has 4 divisors (see below), whose sum is σ = 674100. Its totient is φ = 449392.

The previous prime is 561733. The next prime is 561761. The reversal of 561745 is 547165.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 547165 = 5 ⋅109433.

It can be written as a sum of positive squares in 2 ways, for example, as 322624 + 239121 = 568^2 + 489^2 .

It is a cyclic number.

It is not a de Polignac number, because 561745 - 2⁵ = 561713 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56170 + ... + 56179.

It is an arithmetic number, because the mean of its divisors is an integer number (168525).

2⁵⁶¹⁷⁴⁵ is an apocalyptic number.

It is an amenable number.

561745 is a deficient number, since it is larger than the sum of its proper divisors (112355).

561745 is a wasteful number, since it uses less digits than its factorization.

561745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112354.

The product of its digits is 4200, while the sum is 28.

The square root of 561745 is about 749.4964976569. The cubic root of 561745 is about 82.5112320183.

The spelling of 561745 in words is "five hundred sixty-one thousand, seven hundred forty-five".