18989913 has 8 divisors (see below), whose sum is σ = 25352800. Its totient is φ = 12643488.

The previous prime is 18989909. The next prime is 18989923. The reversal of 18989913 is 31998981.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18989913 - 2² = 18989909 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 7 ways as a sum of consecutive naturals, for example, 1108 + ... + 6261.

It is an arithmetic number, because the mean of its divisors is an integer number (3169100).

Almost surely, 2^18989913 is an apocalyptic number.

It is an amenable number.

18989913 is a deficient number, since it is larger than the sum of its proper divisors (6362887).

18989913 is an equidigital number, since it uses as much as digits as its factorization.

18989913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8231.

The product of its digits is 139968, while the sum is 48.

The square root of 18989913 is about 4357.7417316771. The cubic root of 18989913 is about 266.7929351668.

It can be divided in two parts, 1898 and 9913, that added together give a palindrome (11811).

The spelling of 18989913 in words is "eighteen million, nine hundred eighty-nine thousand, nine hundred thirteen".