16840385 has 4 divisors (see below), whose sum is σ = 20208468. Its totient is φ = 13472304.

The previous prime is 16840367. The next prime is 16840399. The reversal of 16840385 is 58304861.

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 5764801 + 11075584 = 2401^2 + 3328^2 .

It is a cyclic number.

It is not a de Polignac number, because 16840385 - 2⁶ = 16840321 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1684034 + ... + 1684043.

It is an arithmetic number, because the mean of its divisors is an integer number (5052117).

Almost surely, 2^16840385 is an apocalyptic number.

It is an amenable number.

16840385 is a deficient number, since it is larger than the sum of its proper divisors (3368083).

16840385 is an equidigital number, since it uses as much as digits as its factorization.

16840385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3368082.

The product of its (nonzero) digits is 23040, while the sum is 35.

The square root of 16840385 is about 4103.7038148482. The cubic root of 16840385 is about 256.3208917482.

The spelling of 16840385 in words is "sixteen million, eight hundred forty thousand, three hundred eighty-five".