305381 has 4 divisors (see below), whose sum is σ = 315264. Its totient is φ = 295500.

The previous prime is 305377. The next prime is 305401. The reversal of 305381 is 183503.

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 305381 - 2² = 305377 is a prime.

It is a super-2 number, since 2×305381² = 186515110322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (305351) 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, 4895 + ... + 4956.

It is an arithmetic number, because the mean of its divisors is an integer number (78816).

2³⁰⁵³⁸¹ is an apocalyptic number.

305381 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

305381 is a deficient number, since it is larger than the sum of its proper divisors (9883).

305381 is an equidigital number, since it uses as much as digits as its factorization.

305381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9882.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 305381 is about 552.6128843956. The cubic root of 305381 is about 67.3411720661.

Adding to 305381 its reverse (183503), we get a palindrome (488884).

It can be divided in two parts, 305 and 381, that added together give a palindrome (686).

The spelling of 305381 in words is "three hundred five thousand, three hundred eighty-one".