18320550 has 48 divisors (see below), whose sum is σ = 46677072. Its totient is φ = 4752000.

The previous prime is 18320539. The next prime is 18320551. The reversal of 18320550 is 5502381.

It is a self number, because there is not a number n which added to its sum of digits gives 18320550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18320551) 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, 3900 + ... + 7200.

It is an arithmetic number, because the mean of its divisors is an integer number (972439).

Almost surely, 2^18320550 is an apocalyptic number.

18320550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18320550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23338536).

18320550 is an abundant number, since it is smaller than the sum of its proper divisors (28356522).

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

18320550 is a wasteful number, since it uses less digits than its factorization.

18320550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3353 (or 3348 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 18320550 is about 4280.2511608549. The cubic root of 18320550 is about 263.6206961107.

The spelling of 18320550 in words is "eighteen million, three hundred twenty thousand, five hundred fifty".