16866720 has 288 divisors, whose sum is σ = 66869712. Its totient is φ = 3833856.

The previous prime is 16866713. The next prime is 16866727. The reversal of 16866720 is 2766861.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (16866713) and next prime (16866727).

It can be written as a sum of positive squares in 8 ways, for example, as 8363664 + 8503056 = 2892^2 + 2916^2 .

It is a tau number, because it is divible by the number of its divisors (288).

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 (16866727) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 318214 + ... + 318266.

Almost surely, 2^16866720 is an apocalyptic number.

16866720 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 16866720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33434856).

16866720 is an abundant number, since it is smaller than the sum of its proper divisors (50002992).

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

16866720 is a wasteful number, since it uses less digits than its factorization.

16866720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104 (or 93 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 16866720 is about 4106.9112481280. The cubic root of 16866720 is about 256.4544337284.

The spelling of 16866720 in words is "sixteen million, eight hundred sixty-six thousand, seven hundred twenty".