16491994671 has 8 divisors (see below), whose sum is σ = 21993773184. Its totient is φ = 10992439640.

The previous prime is 16491994663. The next prime is 16491994721. The reversal of 16491994671 is 17649919461.

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

It is a cyclic number.

It is not a de Polignac number, because 16491994671 - 2³ = 16491994663 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16491994621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 538485 + ... + 568286.

It is an arithmetic number, because the mean of its divisors is an integer number (2749221648).

Almost surely, 2^16491994671 is an apocalyptic number.

16491994671 is a deficient number, since it is larger than the sum of its proper divisors (5501778513).

16491994671 is a wasteful number, since it uses less digits than its factorization.

16491994671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1111741.

The product of its digits is 2939328, while the sum is 57.

The spelling of 16491994671 in words is "sixteen billion, four hundred ninety-one million, nine hundred ninety-four thousand, six hundred seventy-one".