16866397 has 4 divisors (see below), whose sum is σ = 17858556. Its totient is φ = 15874240.

The previous prime is 16866391. The next prime is 16866419. The reversal of 16866397 is 79366861.

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

It can be written as a sum of positive squares in 2 ways, for example, as 15476356 + 1390041 = 3934^2 + 1179^2 .

It is a cyclic number.

It is not a de Polignac number, because 16866397 - 2¹⁵ = 16833629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16866391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 496054 + ... + 496087.

It is an arithmetic number, because the mean of its divisors is an integer number (4464639).

Almost surely, 2^16866397 is an apocalyptic number.

16866397 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

16866397 is a deficient number, since it is larger than the sum of its proper divisors (992159).

16866397 is an equidigital number, since it uses as much as digits as its factorization.

16866397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 992158.

The product of its digits is 326592, while the sum is 46.

The square root of 16866397 is about 4106.8719239830. The cubic root of 16866397 is about 256.4527966721.

The spelling of 16866397 in words is "sixteen million, eight hundred sixty-six thousand, three hundred ninety-seven".