561537444 has 48 divisors (see below), whose sum is σ = 1414753088. Its totient is φ = 172326528.

The previous prime is 561537443. The next prime is 561537461. The reversal of 561537444 is 444735165.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (561537443) 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, 57399 + ... + 66465.

Almost surely, 2^561537444 is an apocalyptic number.

It is an amenable number.

561537444 is an abundant number, since it is smaller than the sum of its proper divisors (853215644).

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

561537444 is a wasteful number, since it uses less digits than its factorization.

561537444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9484 (or 9482 counting only the distinct ones).

The product of its digits is 201600, while the sum is 39.

The square root of 561537444 is about 23696.7813004214. The cubic root of 561537444 is about 825.0106856284.

The spelling of 561537444 in words is "five hundred sixty-one million, five hundred thirty-seven thousand, four hundred forty-four".