16661699 has 4 divisors (see below), whose sum is σ = 16679040. Its totient is φ = 16644360.

The previous prime is 16661681. The next prime is 16661707. The reversal of 16661699 is 99616661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 16661699 - 2⁸ = 16661443 is a prime.

It is a super-2 number, since 2×16661699² = 555224427133202, which contains 22 as substring.

It is a Duffinian number.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (16661629) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7139 + ... + 9180.

It is an arithmetic number, because the mean of its divisors is an integer number (4169760).

Almost surely, 2^16661699 is an apocalyptic number.

16661699 is a deficient number, since it is larger than the sum of its proper divisors (17341).

16661699 is a wasteful number, since it uses less digits than its factorization.

16661699 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17340.

The product of its digits is 104976, while the sum is 44.

The square root of 16661699 is about 4081.8744468687. The cubic root of 16661699 is about 255.4110964772.

The spelling of 16661699 in words is "sixteen million, six hundred sixty-one thousand, six hundred ninety-nine".