18943830 has 24 divisors (see below), whose sum is σ = 49254192. Its totient is φ = 5051664.

The previous prime is 18943829. The next prime is 18943849. The reversal of 18943830 is 3834981.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

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, 105154 + ... + 105333.

It is an arithmetic number, because the mean of its divisors is an integer number (2052258).

Almost surely, 2^18943830 is an apocalyptic number.

18943830 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18943830 is an abundant number, since it is smaller than the sum of its proper divisors (30310362).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18943830 is a wasteful number, since it uses less digits than its factorization.

18943830 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210500 (or 210497 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 18943830 is about 4352.4510336131. The cubic root of 18943830 is about 266.5769507226.

The spelling of 18943830 in words is "eighteen million, nine hundred forty-three thousand, eight hundred thirty".