312133221 has 12 divisors (see below), whose sum is σ = 463044972. Its totient is φ = 202464576.

The previous prime is 312133201. The next prime is 312133223. The reversal of 312133221 is 122331213.

312133221 is a `hidden beast` number, since 312 + 1 + 332 + 21 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 129072321 + 183060900 = 11361^2 + 13530^2 .

It is not a de Polignac number, because 312133221 - 2¹¹ = 312131173 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 312133194 and 312133203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (312133223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 468336 + ... + 469001.

It is an arithmetic number, because the mean of its divisors is an integer number (38587081).

Almost surely, 2^312133221 is an apocalyptic number.

It is an amenable number.

312133221 is a deficient number, since it is larger than the sum of its proper divisors (150911751).

312133221 is a wasteful number, since it uses less digits than its factorization.

312133221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 937380 (or 937377 counting only the distinct ones).

The product of its digits is 216, while the sum is 18.

The square root of 312133221 is about 17667.2924071574. The cubic root of 312133221 is about 678.3388091782.

Adding to 312133221 its reverse (122331213), we get a palindrome (434464434).

The spelling of 312133221 in words is "three hundred twelve million, one hundred thirty-three thousand, two hundred twenty-one".