16721144 has 32 divisors (see below), whose sum is σ = 34473600. Its totient is φ = 7540320.

The previous prime is 16721141. The next prime is 16721167. The reversal of 16721144 is 44112761.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16721141) 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, 11549 + ... + 12915.

It is an arithmetic number, because the mean of its divisors is an integer number (1077300).

Almost surely, 2^16721144 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16721144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17236800).

16721144 is an abundant number, since it is smaller than the sum of its proper divisors (17752456).

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

16721144 is a wasteful number, since it uses less digits than its factorization.

16721144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1523 (or 1519 counting only the distinct ones).

The product of its digits is 1344, while the sum is 26.

The square root of 16721144 is about 4089.1495448320. The cubic root of 16721144 is about 255.7144847448.

The spelling of 16721144 in words is "sixteen million, seven hundred twenty-one thousand, one hundred forty-four".