18449380 has 48 divisors (see below), whose sum is σ = 41690880. Its totient is φ = 6835968.

The previous prime is 18449357. The next prime is 18449383. The reversal of 18449380 is 8394481.

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (18449383) 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 15 ways as a sum of consecutive naturals, for example, 17344 + ... + 18376.

It is an arithmetic number, because the mean of its divisors is an integer number (868560).

Almost surely, 2^18449380 is an apocalyptic number.

18449380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18449380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20845440).

18449380 is an abundant number, since it is smaller than the sum of its proper divisors (23241500).

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

18449380 is a wasteful number, since it uses less digits than its factorization.

18449380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1108 (or 1106 counting only the distinct ones).

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

The square root of 18449380 is about 4295.2741472460. The cubic root of 18449380 is about 264.2371797201.

The spelling of 18449380 in words is "eighteen million, four hundred forty-nine thousand, three hundred eighty".