312530221 has 4 divisors (see below), whose sum is σ = 328979200. Its totient is φ = 296081244.

The previous prime is 312530219. The next prime is 312530293. The reversal of 312530221 is 122035213.

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 312530221 - 2¹ = 312530219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 16448959 = 312530221 / (3 + 1 + 2 + 5 + 3 + 0 + 2 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (312531221) 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, 8224461 + ... + 8224498.

It is an arithmetic number, because the mean of its divisors is an integer number (82244800).

Almost surely, 2^312530221 is an apocalyptic number.

It is an amenable number.

312530221 is a deficient number, since it is larger than the sum of its proper divisors (16448979).

312530221 is a wasteful number, since it uses less digits than its factorization.

312530221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16448978.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 312530221 is about 17678.5242879602. The cubic root of 312530221 is about 678.6262787542.

Adding to 312530221 its reverse (122035213), we get a palindrome (434565434).

The spelling of 312530221 in words is "three hundred twelve million, five hundred thirty thousand, two hundred twenty-one".