18423020 has 72 divisors (see below), whose sum is σ = 49124880. Its totient is φ = 5738880.

The previous prime is 18423007. The next prime is 18423029. The reversal of 18423020 is 2032481.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 18422983 and 18423001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18423029) 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, 9926 + ... + 11634.

It is an arithmetic number, because the mean of its divisors is an integer number (682290).

Almost surely, 2^18423020 is an apocalyptic number.

18423020 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 18423020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24562440).

18423020 is an abundant number, since it is smaller than the sum of its proper divisors (30701860).

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

18423020 is a wasteful number, since it uses less digits than its factorization.

18423020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1743 (or 1734 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 18423020 is about 4292.2045617608. The cubic root of 18423020 is about 264.1112746405. Note that the first 3 decimals are identical.

The spelling of 18423020 in words is "eighteen million, four hundred twenty-three thousand, twenty".