313121 has 4 divisors (see below), whose sum is σ = 314244. Its totient is φ = 312000.

The previous prime is 313109. The next prime is 313127. The reversal of 313121 is 121313.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 180625 + 132496 = 425^2 + 364^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-313121 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 313121.

It is not an unprimeable number, because it can be changed into a prime (313127) 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, 221 + ... + 821.

It is an arithmetic number, because the mean of its divisors is an integer number (78561).

2³¹³¹²¹ is an apocalyptic number.

It is an amenable number.

313121 is a deficient number, since it is larger than the sum of its proper divisors (1123).

313121 is an equidigital number, since it uses as much as digits as its factorization.

313121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1122.

The product of its digits is 18, while the sum is 11.

The square root of 313121 is about 559.5721579922. The cubic root of 313121 is about 67.9053614281.

Adding to 313121 its reverse (121313), we get a palindrome (434434).

It can be divided in two parts, 31312 and 1, that added together give a palindrome (31313).

The spelling of 313121 in words is "three hundred thirteen thousand, one hundred twenty-one".