16781312 has 52 divisors (see below), whose sum is σ = 35679996. Its totient is φ = 7864320.

The previous prime is 16781299. The next prime is 16781327. The reversal of 16781312 is 21318761.

It can be written as a sum of positive squares in 2 ways, for example, as 12845056 + 3936256 = 3584^2 + 1984^2 .

It is a super-2 number, since 2×16781312² = 563224864882688, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (2) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69512 + ... + 69752.

Almost surely, 2^16781312 is an apocalyptic number.

It is a pronic number, being equal to 4096×4097.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16781312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17839998).

16781312 is an abundant number, since it is smaller than the sum of its proper divisors (18898684).

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

16781312 is an equidigital number, since it uses as much as digits as its factorization.

16781312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282 (or 260 counting only the distinct ones).

The product of its digits is 2016, while the sum is 29.

The square root of 16781312 is about 4096.4999694861. The cubic root of 16781312 is about 256.0208316381.

The spelling of 16781312 in words is "sixteen million, seven hundred eighty-one thousand, three hundred twelve".