16686993 has 8 divisors (see below), whose sum is σ = 22268448. Its totient is φ = 11115104.

The previous prime is 16686961. The next prime is 16687003. The reversal of 16686993 is 39968661.

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 16686993 - 2⁵ = 16686961 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16686893) 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, 4621 + ... + 7397.

It is an arithmetic number, because the mean of its divisors is an integer number (2783556).

Almost surely, 2^16686993 is an apocalyptic number.

It is an amenable number.

16686993 is a deficient number, since it is larger than the sum of its proper divisors (5581455).

16686993 is a wasteful number, since it uses less digits than its factorization.

16686993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4783.

The product of its digits is 419904, while the sum is 48.

The square root of 16686993 is about 4084.9716033285. The cubic root of 16686993 is about 255.5402770184.

The spelling of 16686993 in words is "sixteen million, six hundred eighty-six thousand, nine hundred ninety-three".