16851493 has 2 divisors, whose sum is σ = 16851494. Its totient is φ = 16851492.

The previous prime is 16851487. The next prime is 16851511. The reversal of 16851493 is 39415861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16499844 + 351649 = 4062^2 + 593^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16851493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16851413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8425746 + 8425747.

It is an arithmetic number, because the mean of its divisors is an integer number (8425747).

Almost surely, 2^16851493 is an apocalyptic number.

It is an amenable number.

16851493 is a deficient number, since it is larger than the sum of its proper divisors (1).

16851493 is an equidigital number, since it uses as much as digits as its factorization.

16851493 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 37.

The square root of 16851493 is about 4105.0570032583. The cubic root of 16851493 is about 256.3772361980.

The spelling of 16851493 in words is "sixteen million, eight hundred fifty-one thousand, four hundred ninety-three".