18434720 has 72 divisors (see below), whose sum is σ = 45434844. Its totient is φ = 7067648.

The previous prime is 18434711. The next prime is 18434723. The reversal of 18434720 is 2743481.

It can be written as a sum of positive squares in 6 ways, for example, as 9168784 + 9265936 = 3028^2 + 3044^2 .

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is not an unprimeable number, because it can be changed into a prime (18434723) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 134492 + ... + 134628.

Almost surely, 2^18434720 is an apocalyptic number.

18434720 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 18434720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22717422).

18434720 is an abundant number, since it is smaller than the sum of its proper divisors (27000124).

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

18434720 is a wasteful number, since it uses less digits than its factorization.

18434720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 18434720 is about 4293.5672814106. The cubic root of 18434720 is about 264.1671729677.

The spelling of 18434720 in words is "eighteen million, four hundred thirty-four thousand, seven hundred twenty".