16043681 has 8 divisors (see below), whose sum is σ = 16556904. Its totient is φ = 15534720.

The previous prime is 16043663. The next prime is 16043689. The reversal of 16043681 is 18634061.

It can be written as a sum of positive squares in 4 ways, for example, as 115600 + 15928081 = 340^2 + 3991^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16043681 is a prime.

It is a super-2 number, since 2×16043681² = 514799400059522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16043689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7691 + ... + 9551.

It is an arithmetic number, because the mean of its divisors is an integer number (2069613).

Almost surely, 2^16043681 is an apocalyptic number.

It is an amenable number.

16043681 is a deficient number, since it is larger than the sum of its proper divisors (513223).

16043681 is a wasteful number, since it uses less digits than its factorization.

16043681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2131.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 16043681 is about 4005.4564034577. The cubic root of 16043681 is about 252.2133124980.

The spelling of 16043681 in words is "sixteen million, forty-three thousand, six hundred eighty-one".