16782081 has 4 divisors (see below), whose sum is σ = 22376112. Its totient is φ = 11188052.

The previous prime is 16782071. The next prime is 16782091. The reversal of 16782081 is 18028761.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18028761 = 3 ⋅6009587.

It is an interprime number because it is at equal distance from previous prime (16782071) and next prime (16782091).

It is a cyclic number.

It is not a de Polignac number, because 16782081 - 2⁷ = 16781953 is a prime.

It is a super-2 number, since 2×16782081² = 563276485381122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (16782001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2797011 + ... + 2797016.

It is an arithmetic number, because the mean of its divisors is an integer number (5594028).

Almost surely, 2^16782081 is an apocalyptic number.

It is an amenable number.

16782081 is a deficient number, since it is larger than the sum of its proper divisors (5594031).

16782081 is an equidigital number, since it uses as much as digits as its factorization.

16782081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5594030.

The product of its (nonzero) digits is 5376, while the sum is 33.

The square root of 16782081 is about 4096.5938290243. The cubic root of 16782081 is about 256.0247422782.

The spelling of 16782081 in words is "sixteen million, seven hundred eighty-two thousand, eighty-one".