16209840 has 160 divisors (see below), whose sum is σ = 55442880. Its totient is φ = 3899392.

The previous prime is 16209829. The next prime is 16209841. The reversal of 16209840 is 4890261.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 16209798 and 16209807.

It is not an unprimeable number, because it can be changed into a prime (16209841) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 118252 + ... + 118388.

It is an arithmetic number, because the mean of its divisors is an integer number (346518).

Almost surely, 2^16209840 is an apocalyptic number.

16209840 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 16209840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27721440).

16209840 is an abundant number, since it is smaller than the sum of its proper divisors (39233040).

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

16209840 is a wasteful number, since it uses less digits than its factorization.

16209840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199 (or 193 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 16209840 is about 4026.1445577624. The cubic root of 16209840 is about 253.0810199462.

The spelling of 16209840 in words is "sixteen million, two hundred nine thousand, eight hundred forty".