130805 has 4 divisors (see below), whose sum is σ = 156972. Its totient is φ = 104640.
The previous prime is 130787. The next prime is 130807. The reversal of 130805 is 508031.
130805 is nontrivially palindromic in base 14.
It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 508031 = 41 ⋅12391.
It can be written as a sum of positive squares in 2 ways, for example, as 39601 + 91204 = 199^2 + 302^2 .
It is not a de Polignac number, because 130805 - 216 = 65269 is a prime.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (130807) 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, 13076 + ... + 13085.
It is an arithmetic number, because the mean of its divisors is an integer number (39243).
2130805 is an apocalyptic number.
It is an amenable number.
130805 is a deficient number, since it is larger than the sum of its proper divisors (26167).
130805 is an equidigital number, since it uses as much as digits as its factorization.
130805 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 26166.
The product of its (nonzero) digits is 120, while the sum is 17.
The square root of 130805 is about 361.6697388502. The cubic root of 130805 is about 50.7623183473.
Adding to 130805 its reverse (508031), we get a palindrome (638836).
The spelling of 130805 in words is "one hundred thirty thousand, eight hundred five".
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