18734861 has 2 divisors, whose sum is σ = 18734862. Its totient is φ = 18734860.

The previous prime is 18734851. The next prime is 18734879. The reversal of 18734861 is 16843781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16760836 + 1974025 = 4094^2 + 1405^2 .

It is an emirp because it is prime and its reverse (16843781) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18734861 - 2¹⁰ = 18733837 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18734851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9367430 + 9367431.

It is an arithmetic number, because the mean of its divisors is an integer number (9367431).

Almost surely, 2^18734861 is an apocalyptic number.

It is an amenable number.

18734861 is a deficient number, since it is larger than the sum of its proper divisors (1).

18734861 is an equidigital number, since it uses as much as digits as its factorization.

18734861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 38.

The square root of 18734861 is about 4328.3785647746. The cubic root of 18734861 is about 265.5931226521.

The spelling of 18734861 in words is "eighteen million, seven hundred thirty-four thousand, eight hundred sixty-one".