18385290 has 144 divisors (see below), whose sum is σ = 60821280. Its totient is φ = 3810240.

The previous prime is 18385277. The next prime is 18385351. The reversal of 18385290 is 9258381.

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

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 48321 + ... + 48699.

It is an arithmetic number, because the mean of its divisors is an integer number (422370).

Almost surely, 2^18385290 is an apocalyptic number.

18385290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18385290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30410640).

18385290 is an abundant number, since it is smaller than the sum of its proper divisors (42435990).

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

18385290 is a wasteful number, since it uses less digits than its factorization.

18385290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 417 (or 407 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 18385290 is about 4287.8071318566. The cubic root of 18385290 is about 263.9308531027.

The spelling of 18385290 in words is "eighteen million, three hundred eighty-five thousand, two hundred ninety".