561687 has 12 divisors (see below), whose sum is σ = 871416. Its totient is φ = 320880.

The previous prime is 561667. The next prime is 561703. The reversal of 561687 is 786165.

561687 = 6⁴ + 7⁴ + ... + 19⁴.

It is not a de Polignac number, because 561687 - 2⁷ = 561559 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561607) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1764 + ... + 2057.

It is an arithmetic number, because the mean of its divisors is an integer number (72618).

2⁵⁶¹⁶⁸⁷ is an apocalyptic number.

561687 is a deficient number, since it is larger than the sum of its proper divisors (309729).

561687 is a wasteful number, since it uses less digits than its factorization.

561687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3838 (or 3831 counting only the distinct ones).

The product of its digits is 10080, while the sum is 33.

The square root of 561687 is about 749.4578040157. The cubic root of 561687 is about 82.5083921674.

The spelling of 561687 in words is "five hundred sixty-one thousand, six hundred eighty-seven".