Search a number
-
+
311309 = 1931613
BaseRepresentation
bin1001100000000001101
3120211000222
41030000031
534430214
610401125
72434415
oct1140015
9524028
10311309
111a2989
121301a5
13ab90b
1481645
156238e
hex4c00d

311309 has 4 divisors (see below), whose sum is σ = 313116. Its totient is φ = 309504.

The previous prime is 311303. The next prime is 311323. The reversal of 311309 is 903113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 903113 = 5915307.

It can be written as a sum of positive squares in 2 ways, for example, as 133225 + 178084 = 365^2 + 422^2 .

It is a cyclic number.

It is not a de Polignac number, because 311309 - 24 = 311293 is a prime.

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 (311303) 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, 614 + ... + 999.

It is an arithmetic number, because the mean of its divisors is an integer number (78279).

2311309 is an apocalyptic number.

It is an amenable number.

311309 is a deficient number, since it is larger than the sum of its proper divisors (1807).

311309 is a wasteful number, since it uses less digits than its factorization.

311309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1806.

The product of its (nonzero) digits is 81, while the sum is 17.

The square root of 311309 is about 557.9507146693. The cubic root of 311309 is about 67.7741207578.

The spelling of 311309 in words is "three hundred eleven thousand, three hundred nine".

Divisors: 1 193 1613 311309