18201320 has 16 divisors (see below), whose sum is σ = 40953060. Its totient is φ = 7280512.

The previous prime is 18201317. The next prime is 18201329. The reversal of 18201320 is 2310281.

It can be written as a sum of positive squares in 2 ways, for example, as 18130564 + 70756 = 4258^2 + 266^2 .

It is not an unprimeable number, because it can be changed into a prime (18201329) 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 3 ways as a sum of consecutive naturals, for example, 227477 + ... + 227556.

Almost surely, 2^18201320 is an apocalyptic number.

18201320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18201320 is an abundant number, since it is smaller than the sum of its proper divisors (22751740).

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

18201320 is a wasteful number, since it uses less digits than its factorization.

18201320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 455044 (or 455040 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 18201320 is about 4266.3005051215. The cubic root of 18201320 is about 263.0475705129.

The spelling of 18201320 in words is "eighteen million, two hundred one thousand, three hundred twenty".