16681801 has 2 divisors, whose sum is σ = 16681802. Its totient is φ = 16681800.

The previous prime is 16681799. The next prime is 16681817. The reversal of 16681801 is 10818661.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16605625 + 76176 = 4075^2 + 276^2 .

It is a cyclic number.

It is not a de Polignac number, because 16681801 - 2¹ = 16681799 is a prime.

Together with 16681799, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (16681001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8340900 + 8340901.

It is an arithmetic number, because the mean of its divisors is an integer number (8340901).

Almost surely, 2^16681801 is an apocalyptic number.

It is an amenable number.

16681801 is a deficient number, since it is larger than the sum of its proper divisors (1).

16681801 is an equidigital number, since it uses as much as digits as its factorization.

16681801 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 16681801 is about 4084.3360537546. The cubic root of 16681801 is about 255.5137712893.

The spelling of 16681801 in words is "sixteen million, six hundred eighty-one thousand, eight hundred one".