561549996 has 240 divisors, whose sum is σ = 1778022400. Its totient is φ = 154314720.

The previous prime is 561549983. The next prime is 561550007. The reversal of 561549996 is 699945165.

561549996 is a `hidden beast` number, since 5 + 6 + 1 + 549 + 9 + 96 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3445011 + ... + 3445173.

Almost surely, 2^561549996 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 561549996, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (889011200).

561549996 is an abundant number, since it is smaller than the sum of its proper divisors (1216472404).

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

561549996 is a wasteful number, since it uses less digits than its factorization.

561549996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231 (or 206 counting only the distinct ones).

The product of its digits is 2624400, while the sum is 54.

The square root of 561549996 is about 23697.0461450367. The cubic root of 561549996 is about 825.0168327144.

It can be divided in two parts, 5615 and 49996, that added together give a triangular number (55611 = T₃₃₃).

The spelling of 561549996 in words is "five hundred sixty-one million, five hundred forty-nine thousand, nine hundred ninety-six".