16643081 has 16 divisors (see below), whose sum is σ = 21041664. Its totient is φ = 12809664.

The previous prime is 16643023. The next prime is 16643087. The reversal of 16643081 is 18034661.

It is a de Polignac number, because none of the positive numbers 2^k-16643081 is a prime.

It is a super-2 number, since 2×16643081² = 553984290345122, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16643087) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 896 + ... + 5838.

It is an arithmetic number, because the mean of its divisors is an integer number (1315104).

Almost surely, 2^16643081 is an apocalyptic number.

It is an amenable number.

16643081 is a deficient number, since it is larger than the sum of its proper divisors (4398583).

16643081 is a wasteful number, since it uses less digits than its factorization.

16643081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5000.

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

The square root of 16643081 is about 4079.5932395277. The cubic root of 16643081 is about 255.3159277895.

The spelling of 16643081 in words is "sixteen million, six hundred forty-three thousand, eighty-one".