313687681 has 4 divisors (see below), whose sum is σ = 318830164. Its totient is φ = 308545200.

The previous prime is 313687669. The next prime is 313687687. The reversal of 313687681 is 186786313.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 117939600 + 195748081 = 10860^2 + 13991^2 .

It is a cyclic number.

It is not a de Polignac number, because 313687681 - 2¹¹ = 313685633 is a prime.

It is a super-2 number, since 2×313687681² = 196799922422315522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (313687687) 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, 2571150 + ... + 2571271.

It is an arithmetic number, because the mean of its divisors is an integer number (79707541).

Almost surely, 2^313687681 is an apocalyptic number.

It is an amenable number.

313687681 is a deficient number, since it is larger than the sum of its proper divisors (5142483).

313687681 is an equidigital number, since it uses as much as digits as its factorization.

313687681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5142482.

The product of its digits is 145152, while the sum is 43.

The square root of 313687681 is about 17711.2303638115. The cubic root of 313687681 is about 679.4630139220.

The spelling of 313687681 in words is "three hundred thirteen million, six hundred eighty-seven thousand, six hundred eighty-one".