18261800 has 24 divisors (see below), whose sum is σ = 42459150. Its totient is φ = 7304640.

The previous prime is 18261787. The next prime is 18261809. The reversal of 18261800 is 816281.

It can be written as a sum of positive squares in 3 ways, for example, as 7279204 + 10982596 = 2698^2 + 3314^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 18261800.

It is not an unprimeable number, because it can be changed into a prime (18261809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 45455 + ... + 45854.

Almost surely, 2^18261800 is an apocalyptic number.

18261800 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18261800 is an abundant number, since it is smaller than the sum of its proper divisors (24197350).

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

18261800 is a wasteful number, since it uses less digits than its factorization.

18261800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91325 (or 91316 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 26.

The square root of 18261800 is about 4273.3827350239. The cubic root of 18261800 is about 263.3386030386.

The spelling of 18261800 in words is "eighteen million, two hundred sixty-one thousand, eight hundred".