561345123 has 6 divisors (see below), whose sum is σ = 748514884. Its totient is φ = 374202724.

The previous prime is 561345077. The next prime is 561345131. The reversal of 561345123 is 321543165.

561345123 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 561345123 - 2⁸ = 561344867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (561345143) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 34198 + ... + 47876.

Almost surely, 2^561345123 is an apocalyptic number.

561345123 is a deficient number, since it is larger than the sum of its proper divisors (187169761).

561345123 is an frugal number, since it uses more digits than its factorization.

561345123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27361 (or 13682 counting only the distinct ones).

The product of its digits is 10800, while the sum is 30.

The square root of 561345123 is about 23692.7229967347. The cubic root of 561345123 is about 824.9164888838.

Multiplying 561345123 by its product of digits (10800), we get a square (6062527328400 = 2462220²).

Adding to 561345123 its reverse (321543165), we get a palindrome (882888288).

The spelling of 561345123 in words is "five hundred sixty-one million, three hundred forty-five thousand, one hundred twenty-three".