16858321 has 2 divisors, whose sum is σ = 16858322. Its totient is φ = 16858320.

The previous prime is 16858313. The next prime is 16858351. The reversal of 16858321 is 12385861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16516096 + 342225 = 4064^2 + 585^2 .

It is a cyclic number.

It is not a de Polignac number, because 16858321 - 2³ = 16858313 is a prime.

It is not a weakly prime, because it can be changed into another prime (16858351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8429160 + 8429161.

It is an arithmetic number, because the mean of its divisors is an integer number (8429161).

Almost surely, 2^16858321 is an apocalyptic number.

It is an amenable number.

16858321 is a deficient number, since it is larger than the sum of its proper divisors (1).

16858321 is an equidigital number, since it uses as much as digits as its factorization.

16858321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11520, while the sum is 34.

The square root of 16858321 is about 4105.8885761793. Note that the first 3 decimals coincide. The cubic root of 16858321 is about 256.4118584002.

The spelling of 16858321 in words is "sixteen million, eight hundred fifty-eight thousand, three hundred twenty-one".