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18230881 = 23792647
BaseRepresentation
bin100010110001…
…0111001100001
31021022020001211
41011202321201
514131342011
61450430121
7310650154
oct105427141
937266054
1018230881
11a322149
126132341
133a14106
1425c7c9b
151901b21
hex1162e61

18230881 has 4 divisors (see below), whose sum is σ = 19023552. Its totient is φ = 17438212.

The previous prime is 18230873. The next prime is 18230893. The reversal of 18230881 is 18803281.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18230881 - 23 = 18230873 is a prime.

It is a super-2 number, since 2×182308812 = 664730044072322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18230081) 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 3 ways as a sum of consecutive naturals, for example, 396301 + ... + 396346.

It is an arithmetic number, because the mean of its divisors is an integer number (4755888).

Almost surely, 218230881 is an apocalyptic number.

It is an amenable number.

18230881 is a deficient number, since it is larger than the sum of its proper divisors (792671).

18230881 is an equidigital number, since it uses as much as digits as its factorization.

18230881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 792670.

The product of its (nonzero) digits is 3072, while the sum is 31.

The square root of 18230881 is about 4269.7635765930. The cubic root of 18230881 is about 263.1898998120.

The spelling of 18230881 in words is "eighteen million, two hundred thirty thousand, eight hundred eighty-one".

Divisors: 1 23 792647 18230881