561686400 has 480 divisors, whose sum is σ = 2272655880. Its totient is φ = 135475200.

The previous prime is 561686399. The next prime is 561686407. The reversal of 561686400 is 4686165.

561686400 is a `hidden beast` number, since 5 + 6 + 1 + 6 + 8 + 640 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a super-2 number, since 2×561686400² = 630983223889920000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561686407) by changing a digit.

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 59 ways as a sum of consecutive naturals, for example, 2851102 + ... + 2851298.

Almost surely, 2^561686400 is an apocalyptic number.

561686400 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 561686400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1136327940).

561686400 is an abundant number, since it is smaller than the sum of its proper divisors (1710969480).

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

561686400 is a wasteful number, since it uses less digits than its factorization.

561686400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244 (or 218 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 561686400 is about 23699.9240505112. The cubic root of 561686400 is about 825.0836278862.

The spelling of 561686400 in words is "five hundred sixty-one million, six hundred eighty-six thousand, four hundred".