16664287 has 4 divisors (see below), whose sum is σ = 16820136. Its totient is φ = 16508440.

The previous prime is 16664261. The next prime is 16664317. The reversal of 16664287 is 78246661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78246661 = 6361 ⋅12301.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16664287 is a prime.

It is a super-2 number, since 2×16664287² = 555396922436738, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16664587) 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 3 ways as a sum of consecutive naturals, for example, 77764 + ... + 77977.

It is an arithmetic number, because the mean of its divisors is an integer number (4205034).

Almost surely, 2^16664287 is an apocalyptic number.

16664287 is a deficient number, since it is larger than the sum of its proper divisors (155849).

16664287 is a wasteful number, since it uses less digits than its factorization.

16664287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155848.

The product of its digits is 96768, while the sum is 40.

The square root of 16664287 is about 4082.1914457801. The cubic root of 16664287 is about 255.4243198125.

The spelling of 16664287 in words is "sixteen million, six hundred sixty-four thousand, two hundred eighty-seven".