16121728 has 64 divisors (see below), whose sum is σ = 38678400. Its totient is φ = 6538752.

The previous prime is 16121719. The next prime is 16121753. The reversal of 16121728 is 82712161.

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

It is a super-2 number, since 2×16121728² = 519820227411968, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 16121696 and 16121705.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16551 + ... + 17497.

It is an arithmetic number, because the mean of its divisors is an integer number (604350).

Almost surely, 2^16121728 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 16121728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19339200).

16121728 is an abundant number, since it is smaller than the sum of its proper divisors (22556672).

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

16121728 is an equidigital number, since it uses as much as digits as its factorization.

16121728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 987 (or 975 counting only the distinct ones).

The product of its digits is 1344, while the sum is 28.

The square root of 16121728 is about 4015.1871687382. The cubic root of 16121728 is about 252.6216281656.

Adding to 16121728 its reverse (82712161), we get a palindrome (98833889).

The spelling of 16121728 in words is "sixteen million, one hundred twenty-one thousand, seven hundred twenty-eight".