561404 has 6 divisors (see below), whose sum is σ = 982464. Its totient is φ = 280700.

The previous prime is 561389. The next prime is 561409. The reversal of 561404 is 404165.

It is a happy number.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 70172 + ... + 70179.

It is an arithmetic number, because the mean of its divisors is an integer number (163744).

2⁵⁶¹⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

561404 is a deficient number, since it is larger than the sum of its proper divisors (421060).

561404 is a wasteful number, since it uses less digits than its factorization.

561404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140355 (or 140353 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 561404 is about 749.2689770703. The cubic root of 561404 is about 82.4945328486.

Adding to 561404 its reverse (404165), we get a palindrome (965569).

The spelling of 561404 in words is "five hundred sixty-one thousand, four hundred four".