18894481 has 4 divisors (see below), whose sum is σ = 19355364. Its totient is φ = 18433600.

The previous prime is 18894461. The next prime is 18894503. The reversal of 18894481 is 18449881.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2822400 + 16072081 = 1680^2 + 4009^2 .

It is a de Polignac number, because none of the positive numbers 2^k-18894481 is a prime.

It is a super-2 number, since 2×18894481² = 714002824518722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18894401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 230380 + ... + 230461.

It is an arithmetic number, because the mean of its divisors is an integer number (4838841).

Almost surely, 2^18894481 is an apocalyptic number.

It is an amenable number.

18894481 is a deficient number, since it is larger than the sum of its proper divisors (460883).

18894481 is an equidigital number, since it uses as much as digits as its factorization.

18894481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 460882.

The product of its digits is 73728, while the sum is 43.

The square root of 18894481 is about 4346.7782322083. The cubic root of 18894481 is about 266.3452702622.

The spelling of 18894481 in words is "eighteen million, eight hundred ninety-four thousand, four hundred eighty-one".