16997643 has 24 divisors (see below), whose sum is σ = 26666640. Its totient is φ = 10370880.

The previous prime is 16997639. The next prime is 16997677. The reversal of 16997643 is 34679961.

It is not a de Polignac number, because 16997643 - 2² = 16997639 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16997623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14773 + ... + 15881.

It is an arithmetic number, because the mean of its divisors is an integer number (1111110).

Almost surely, 2^16997643 is an apocalyptic number.

16997643 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

16997643 is a deficient number, since it is larger than the sum of its proper divisors (9668997).

16997643 is a wasteful number, since it uses less digits than its factorization.

16997643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1259 (or 1256 counting only the distinct ones).

The product of its digits is 244944, while the sum is 45.

The square root of 16997643 is about 4122.8197874756. The cubic root of 16997643 is about 257.1162751623.

The spelling of 16997643 in words is "sixteen million, nine hundred ninety-seven thousand, six hundred forty-three".