18261000 has 96 divisors (see below), whose sum is σ = 61752600. Its totient is φ = 4867200.

The previous prime is 18260989. The next prime is 18261013. The reversal of 18261000 is 16281.

It can be written as a sum of positive squares in 4 ways, for example, as 11573604 + 6687396 = 3402^2 + 2586^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

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, 7986 + ... + 10014.

Almost surely, 2^18261000 is an apocalyptic number.

18261000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18261000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30876300).

18261000 is an abundant number, since it is smaller than the sum of its proper divisors (43491600).

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

18261000 is a wasteful number, since it uses less digits than its factorization.

18261000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2056 (or 2039 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 18261000 is about 4273.2891313367. The cubic root of 18261000 is about 263.3347575988.

Adding to 18261000 its reverse (16281), we get a palindrome (18277281).

The spelling of 18261000 in words is "eighteen million, two hundred sixty-one thousand".