18227681 has 8 divisors (see below), whose sum is σ = 18675840. Its totient is φ = 17782128.

The previous prime is 18227653. The next prime is 18227683. The reversal of 18227681 is 18672281.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18227681 is a prime.

It is a super-3 number, since 3×18227681³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18227683) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25355 + ... + 26063.

It is an arithmetic number, because the mean of its divisors is an integer number (2334480).

Almost surely, 2^18227681 is an apocalyptic number.

It is an amenable number.

18227681 is a deficient number, since it is larger than the sum of its proper divisors (448159).

18227681 is an equidigital number, since it uses as much as digits as its factorization.

18227681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1303.

The product of its digits is 10752, while the sum is 35.

The square root of 18227681 is about 4269.3888321398. The cubic root of 18227681 is about 263.1744999901.

The spelling of 18227681 in words is "eighteen million, two hundred twenty-seven thousand, six hundred eighty-one".