18989963 has 4 divisors (see below), whose sum is σ = 19005168. Its totient is φ = 18974760.

The previous prime is 18989959. The next prime is 18990017. The reversal of 18989963 is 36998981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36998981 = 2963 ⋅12487.

It is a cyclic number.

It is not a de Polignac number, because 18989963 - 2² = 18989959 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18989923) 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 in 3 ways as a sum of consecutive naturals, for example, 5543 + ... + 8288.

It is an arithmetic number, because the mean of its divisors is an integer number (4751292).

Almost surely, 2^18989963 is an apocalyptic number.

18989963 is a deficient number, since it is larger than the sum of its proper divisors (15205).

18989963 is a wasteful number, since it uses less digits than its factorization.

18989963 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15204.

The product of its digits is 839808, while the sum is 53.

The square root of 18989963 is about 4357.7474685897. The cubic root of 18989963 is about 266.7931693198.

The spelling of 18989963 in words is "eighteen million, nine hundred eighty-nine thousand, nine hundred sixty-three".