16809856 has 64 divisors (see below), whose sum is σ = 38947680. Its totient is φ = 7077888.

The previous prime is 16809853. The next prime is 16809869. The reversal of 16809856 is 65890861.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16809853) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65280 + ... + 65536.

Almost surely, 2^16809856 is an apocalyptic number.

16809856 is a gapful number since it is divisible by the number (16) 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 16809856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19473840).

16809856 is an abundant number, since it is smaller than the sum of its proper divisors (22137824).

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

16809856 is an equidigital number, since it uses as much as digits as its factorization.

16809856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351 (or 339 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 43.

The square root of 16809856 is about 4099.9824389868. The cubic root of 16809856 is about 256.1659080803.

The spelling of 16809856 in words is "sixteen million, eight hundred nine thousand, eight hundred fifty-six".