18001788 has 48 divisors (see below), whose sum is σ = 49185024. Its totient is φ = 5016960.

The previous prime is 18001729. The next prime is 18001811. The reversal of 18001788 is 88710081.

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 831 + ... + 6057.

It is an arithmetic number, because the mean of its divisors is an integer number (1024688).

Almost surely, 2^18001788 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18001788, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24592512).

18001788 is an abundant number, since it is smaller than the sum of its proper divisors (31183236).

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

18001788 is a wasteful number, since it uses less digits than its factorization.

18001788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5282 (or 5280 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 33.

The square root of 18001788 is about 4242.8513997075. The cubic root of 18001788 is about 262.0828166995.

The spelling of 18001788 in words is "eighteen million, one thousand, seven hundred eighty-eight".