312720321 has 8 divisors (see below), whose sum is σ = 441487584. Its totient is φ = 196216640.

The previous prime is 312720319. The next prime is 312720323. The reversal of 312720321 is 123027213.

It is an interprime number because it is at equal distance from previous prime (312720319) and next prime (312720323).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 312720321 - 2¹ = 312720319 is a prime.

It is not an unprimeable number, because it can be changed into a prime (312720323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3065835 + ... + 3065936.

It is an arithmetic number, because the mean of its divisors is an integer number (55185948).

Almost surely, 2^312720321 is an apocalyptic number.

It is an amenable number.

312720321 is a deficient number, since it is larger than the sum of its proper divisors (128767263).

312720321 is a wasteful number, since it uses less digits than its factorization.

312720321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6131791.

The product of its (nonzero) digits is 504, while the sum is 21.

The square root of 312720321 is about 17683.9000506110. The cubic root of 312720321 is about 678.7638448722.

Adding to 312720321 its reverse (123027213), we get a palindrome (435747534).

The spelling of 312720321 in words is "three hundred twelve million, seven hundred twenty thousand, three hundred twenty-one".