18898643 has 2 divisors, whose sum is σ = 18898644. Its totient is φ = 18898642.

The previous prime is 18898639. The next prime is 18898657. The reversal of 18898643 is 34689881.

It is a weak prime.

It is an emirp because it is prime and its reverse (34689881) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18898643 - 2² = 18898639 is a prime.

It is not a weakly prime, because it can be changed into another prime (18898843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9449321 + 9449322.

It is an arithmetic number, because the mean of its divisors is an integer number (9449322).

Almost surely, 2^18898643 is an apocalyptic number.

18898643 is a deficient number, since it is larger than the sum of its proper divisors (1).

18898643 is an equidigital number, since it uses as much as digits as its factorization.

18898643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 331776, while the sum is 47.

The square root of 18898643 is about 4347.2569512280. The cubic root of 18898643 is about 266.3648253134.

The spelling of 18898643 in words is "eighteen million, eight hundred ninety-eight thousand, six hundred forty-three".