18001680 has 80 divisors (see below), whose sum is σ = 56407104. Its totient is φ = 4748800.

The previous prime is 18001673. The next prime is 18001681. The reversal of 18001680 is 8610081.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 18001680.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18001681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25330 + ... + 26030.

Almost surely, 2^18001680 is an apocalyptic number.

18001680 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 18001680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28203552).

18001680 is an abundant number, since it is smaller than the sum of its proper divisors (38405424).

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

18001680 is a wasteful number, since it uses less digits than its factorization.

18001680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 824 (or 818 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 24.

The square root of 18001680 is about 4242.8386723985. The cubic root of 18001680 is about 262.0822925849.

It can be divided in two parts, 18001 and 680, that added together give a palindrome (18681).

The spelling of 18001680 in words is "eighteen million, one thousand, six hundred eighty".