561644 has 6 divisors (see below), whose sum is σ = 982884. Its totient is φ = 280820.

The previous prime is 561607. The next prime is 561667. The reversal of 561644 is 446165.

It is a happy number.

It is a super-3 number, since 3×561644³ = 531501660719333952, which contains 333 as substring.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 561644.

It is an unprimeable number.

561644 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 70202 + ... + 70209.

It is an arithmetic number, because the mean of its divisors is an integer number (163814).

2⁵⁶¹⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

561644 is a deficient number, since it is larger than the sum of its proper divisors (421240).

561644 is a wasteful number, since it uses less digits than its factorization.

561644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140415 (or 140413 counting only the distinct ones).

The product of its digits is 2880, while the sum is 26.

The square root of 561644 is about 749.4291160610. The cubic root of 561644 is about 82.5062866345.

The spelling of 561644 in words is "five hundred sixty-one thousand, six hundred forty-four".