313320721 has 4 divisors (see below), whose sum is σ = 358080832. Its totient is φ = 268560612.

The previous prime is 313320713. The next prime is 313320797. The reversal of 313320721 is 127023313.

It is a happy number.

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 313320721 - 2³ = 313320713 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 313320692 and 313320701.

It is not an unprimeable number, because it can be changed into a prime (313320701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22380045 + ... + 22380058.

It is an arithmetic number, because the mean of its divisors is an integer number (89520208).

Almost surely, 2^313320721 is an apocalyptic number.

It is an amenable number.

313320721 is a deficient number, since it is larger than the sum of its proper divisors (44760111).

313320721 is an equidigital number, since it uses as much as digits as its factorization.

313320721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44760110.

The product of its (nonzero) digits is 756, while the sum is 22.

The square root of 313320721 is about 17700.8678035852. The cubic root of 313320721 is about 679.1979593763.

The spelling of 313320721 in words is "three hundred thirteen million, three hundred twenty thousand, seven hundred twenty-one".