561605555436 has 24 divisors (see below), whose sum is σ = 1387496078640. Its totient is φ = 176189978112.

The previous prime is 561605555431. The next prime is 561605555473. The reversal of 561605555436 is 634555506165.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (561605555431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1376484001 + ... + 1376484408.

It is an arithmetic number, because the mean of its divisors is an integer number (57812336610).

Almost surely, 2^561605555436 is an apocalyptic number.

It is an amenable number.

561605555436 is an abundant number, since it is smaller than the sum of its proper divisors (825890523204).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

561605555436 is a wasteful number, since it uses less digits than its factorization.

561605555436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2752968433 (or 2752968431 counting only the distinct ones).

The product of its (nonzero) digits is 8100000, while the sum is 51.

The spelling of 561605555436 in words is "five hundred sixty-one billion, six hundred five million, five hundred fifty-five thousand, four hundred thirty-six".