18418428 has 72 divisors (see below), whose sum is σ = 55199872. Its totient is φ = 5260464.

The previous prime is 18418427. The next prime is 18418441. The reversal of 18418428 is 82481481.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 18418392 and 18418401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18418427) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5451 + ... + 8157.

Almost surely, 2^18418428 is an apocalyptic number.

18418428 is a gapful number since it is divisible by the number (18) 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 18418428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27599936).

18418428 is an abundant number, since it is smaller than the sum of its proper divisors (36781444).

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

18418428 is a wasteful number, since it uses less digits than its factorization.

18418428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2733 (or 2719 counting only the distinct ones).

The product of its digits is 16384, while the sum is 36.

The square root of 18418428 is about 4291.6696051770. The cubic root of 18418428 is about 264.0893292745.

The spelling of 18418428 in words is "eighteen million, four hundred eighteen thousand, four hundred twenty-eight".