16681971 has 8 divisors (see below), whose sum is σ = 22355200. Its totient is φ = 11065032.

The previous prime is 16681949. The next prime is 16681991. The reversal of 16681971 is 17918661.

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

It is not a de Polignac number, because 16681971 - 2⁵ = 16681939 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16681901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13375 + ... + 14568.

It is an arithmetic number, because the mean of its divisors is an integer number (2794400).

Almost surely, 2^16681971 is an apocalyptic number.

16681971 is a deficient number, since it is larger than the sum of its proper divisors (5673229).

16681971 is a wasteful number, since it uses less digits than its factorization.

16681971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28145.

The product of its digits is 18144, while the sum is 39.

The square root of 16681971 is about 4084.3568649177. The cubic root of 16681971 is about 255.5146392451.

The spelling of 16681971 in words is "sixteen million, six hundred eighty-one thousand, nine hundred seventy-one".