16809408 has 168 divisors, whose sum is σ = 60228480. Its totient is φ = 4354560.

The previous prime is 16809407. The next prime is 16809437. The reversal of 16809408 is 80490861.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (168).

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 (16809407) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 44163 + ... + 44541.

Almost surely, 2^16809408 is an apocalyptic number.

16809408 is a gapful number since it is divisible by the number (18) 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 16809408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30114240).

16809408 is an abundant number, since it is smaller than the sum of its proper divisors (43419072).

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

16809408 is a wasteful number, since it uses less digits than its factorization.

16809408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415 (or 402 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 16809408 is about 4099.9278042424. The cubic root of 16809408 is about 256.1636323649.

The spelling of 16809408 in words is "sixteen million, eight hundred nine thousand, four hundred eight".