16568640 has 168 divisors, whose sum is σ = 62288928. Its totient is φ = 4008960.

The previous prime is 16568623. The next prime is 16568641. The reversal of 16568640 is 4686561.

16568640 is a `hidden beast` number, since 1 + 6 + 5 + 6 + 8 + 640 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 16568595 and 16568604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16568641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31419 + ... + 31941.

Almost surely, 2^16568640 is an apocalyptic number.

16568640 is a gapful number since it is divisible by the number (10) 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 16568640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31144464).

16568640 is an abundant number, since it is smaller than the sum of its proper divisors (45720288).

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

16568640 is a wasteful number, since it uses less digits than its factorization.

16568640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 557 (or 544 counting only the distinct ones).

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

The square root of 16568640 is about 4070.4594335284. The cubic root of 16568640 is about 254.9347006962.

It can be divided in two parts, 1656 and 8640, that added together give a triangular number (10296 = T₁₄₃).

The spelling of 16568640 in words is "sixteen million, five hundred sixty-eight thousand, six hundred forty".