312120211 has 4 divisors (see below), whose sum is σ = 336129472. Its totient is φ = 288110952.

The previous prime is 312120203. The next prime is 312120217. The reversal of 312120211 is 112021213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 112021213 = 2447 ⋅45779.

It is a cyclic number.

It is not a de Polignac number, because 312120211 - 2³ = 312120203 is a prime.

It is a super-2 number, since 2×312120211² = 194838052229369042, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 24009247 = 312120211 / (3 + 1 + 2 + 1 + 2 + 0 + 2 + 1 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 312120191 and 312120200.

It is not an unprimeable number, because it can be changed into a prime (312120217) 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, 12004611 + ... + 12004636.

It is an arithmetic number, because the mean of its divisors is an integer number (84032368).

Almost surely, 2^312120211 is an apocalyptic number.

312120211 is a deficient number, since it is larger than the sum of its proper divisors (24009261).

312120211 is a wasteful number, since it uses less digits than its factorization.

312120211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24009260.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 312120211 is about 17666.9242088146. The cubic root of 312120211 is about 678.3293844519.

Adding to 312120211 its reverse (112021213), we get a palindrome (424141424).

It can be divided in two parts, 3121202 and 11, that added together give a palindrome (3121213).

The spelling of 312120211 in words is "three hundred twelve million, one hundred twenty thousand, two hundred eleven".