18019422 has 56 divisors (see below), whose sum is σ = 42968016. Its totient is φ = 5645376.

The previous prime is 18019387. The next prime is 18019423. The reversal of 18019422 is 22491081.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18019423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 24423 + ... + 25149.

It is an arithmetic number, because the mean of its divisors is an integer number (767286).

Almost surely, 2^18019422 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18019422, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21484008).

18019422 is an abundant number, since it is smaller than the sum of its proper divisors (24948594).

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

18019422 is an equidigital number, since it uses as much as digits as its factorization.

18019422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 764 (or 749 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 18019422 is about 4244.9289746708. The cubic root of 18019422 is about 262.1683648714.

The spelling of 18019422 in words is "eighteen million, nineteen thousand, four hundred twenty-two".