561661603 has 16 divisors (see below), whose sum is σ = 602208000. Its totient is φ = 522273312.

The previous prime is 561661601. The next prime is 561661619. The reversal of 561661603 is 306166165.

It is a cyclic number.

It is not a de Polignac number, because 561661603 - 2¹ = 561661601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (561661601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 456393 + ... + 457621.

It is an arithmetic number, because the mean of its divisors is an integer number (37638000).

Almost surely, 2^561661603 is an apocalyptic number.

561661603 is a deficient number, since it is larger than the sum of its proper divisors (40546397).

561661603 is a wasteful number, since it uses less digits than its factorization.

561661603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1674.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 561661603 is about 23699.4008996008. The cubic root of 561661603 is about 825.0714859390.

The spelling of 561661603 in words is "five hundred sixty-one million, six hundred sixty-one thousand, six hundred three".