18943801 has 2 divisors, whose sum is σ = 18943802. Its totient is φ = 18943800.

The previous prime is 18943783. The next prime is 18943807. The reversal of 18943801 is 10834981.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18481401 + 462400 = 4299^2 + 680^2 .

It is an emirp because it is prime and its reverse (10834981) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18943801 is a prime.

It is not a weakly prime, because it can be changed into another prime (18943807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9471900 + 9471901.

It is an arithmetic number, because the mean of its divisors is an integer number (9471901).

Almost surely, 2^18943801 is an apocalyptic number.

It is an amenable number.

18943801 is a deficient number, since it is larger than the sum of its proper divisors (1).

18943801 is an equidigital number, since it uses as much as digits as its factorization.

18943801 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 18943801 is about 4352.4477021557. The cubic root of 18943801 is about 266.5768146935.

The spelling of 18943801 in words is "eighteen million, nine hundred forty-three thousand, eight hundred one".