561503837 has 4 divisors (see below), whose sum is σ = 579616896. Its totient is φ = 543390780.

The previous prime is 561503791. The next prime is 561503843. The reversal of 561503837 is 738305165.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 561503837 - 2¹⁴ = 561487453 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 561503837.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561503857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9056483 + ... + 9056544.

It is an arithmetic number, because the mean of its divisors is an integer number (144904224).

Almost surely, 2^561503837 is an apocalyptic number.

It is an amenable number.

561503837 is a deficient number, since it is larger than the sum of its proper divisors (18113059).

561503837 is a wasteful number, since it uses less digits than its factorization.

561503837 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18113058.

The product of its (nonzero) digits is 75600, while the sum is 38.

The square root of 561503837 is about 23696.0721850690. The cubic root of 561503837 is about 824.9942268344.

The spelling of 561503837 in words is "five hundred sixty-one million, five hundred three thousand, eight hundred thirty-seven".