18420324 has 72 divisors (see below), whose sum is σ = 48206592. Its totient is φ = 5466240.

The previous prime is 18420319. The next prime is 18420341. The reversal of 18420324 is 42302481.

18420324 = 105² + 106² + ... + 383².

It is a junction number, because it is equal to n+sod(n) for n = 18420294 and 18420303.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 62722 + ... + 63014.

It is an arithmetic number, because the mean of its divisors is an integer number (669536).

Almost surely, 2^18420324 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 18420324, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24103296).

18420324 is an abundant number, since it is smaller than the sum of its proper divisors (29786268).

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

18420324 is a wasteful number, since it uses less digits than its factorization.

18420324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357 (or 342 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 18420324 is about 4291.8904925452. The cubic root of 18420324 is about 264.0983907823.

The spelling of 18420324 in words is "eighteen million, four hundred twenty thousand, three hundred twenty-four".