18384490 has 16 divisors (see below), whose sum is σ = 33216552. Its totient is φ = 7326144.

The previous prime is 18384479. The next prime is 18384491. The reversal of 18384490 is 9448381.

It can be written as a sum of positive squares in 4 ways, for example, as 5803281 + 12581209 = 2409^2 + 3547^2 .

It is not an unprimeable number, because it can be changed into a prime (18384491) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 549 + ... + 6088.

Almost surely, 2^18384490 is an apocalyptic number.

18384490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18384490 is a deficient number, since it is larger than the sum of its proper divisors (14832062).

18384490 is a wasteful number, since it uses less digits than its factorization.

18384490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6921.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 18384490 is about 4287.7138430637. The cubic root of 18384490 is about 263.9270249020.

It can be divided in two parts, 1838 and 4490, that added together give a triangular number (6328 = T₁₁₂).

The spelling of 18384490 in words is "eighteen million, three hundred eighty-four thousand, four hundred ninety".