18643018 has 24 divisors (see below), whose sum is σ = 29782368. Its totient is φ = 8749752.

The previous prime is 18643007. The next prime is 18643019. The reversal of 18643018 is 81034681.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (18643019) 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 11 ways as a sum of consecutive naturals, for example, 70755 + ... + 71017.

It is an arithmetic number, because the mean of its divisors is an integer number (1240932).

Almost surely, 2^18643018 is an apocalyptic number.

18643018 is a deficient number, since it is larger than the sum of its proper divisors (11139350).

18643018 is a wasteful number, since it uses less digits than its factorization.

18643018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378 (or 355 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 18643018 is about 4317.7561302139. The cubic root of 18643018 is about 265.1584100937.

Adding to 18643018 its reverse (81034681), we get a palindrome (99677699).

The spelling of 18643018 in words is "eighteen million, six hundred forty-three thousand, eighteen".