18236380 has 12 divisors (see below), whose sum is σ = 38296440. Its totient is φ = 7294544.

The previous prime is 18236363. The next prime is 18236381. The reversal of 18236380 is 8363281.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18236381) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 455890 + ... + 455929.

It is an arithmetic number, because the mean of its divisors is an integer number (3191370).

Almost surely, 2^18236380 is an apocalyptic number.

18236380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18236380 is an abundant number, since it is smaller than the sum of its proper divisors (20060060).

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

18236380 is a wasteful number, since it uses less digits than its factorization.

18236380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 911828 (or 911826 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 18236380 is about 4270.4074747031. The cubic root of 18236380 is about 263.2163592348.

The spelling of 18236380 in words is "eighteen million, two hundred thirty-six thousand, three hundred eighty".