312331666 has 4 divisors (see below), whose sum is σ = 468497502. Its totient is φ = 156165832.

The previous prime is 312331637. The next prime is 312331673. The reversal of 312331666 is 666133213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 666133213 = 173 ⋅3850481.

It can be written as a sum of positive squares in only one way, i.e., 310781641 + 1550025 = 17629^2 + 1245^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78082915 + ... + 78082918.

Almost surely, 2^312331666 is an apocalyptic number.

312331666 is a deficient number, since it is larger than the sum of its proper divisors (156165836).

312331666 is a wasteful number, since it uses less digits than its factorization.

312331666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156165835.

The product of its digits is 11664, while the sum is 31.

The square root of 312331666 is about 17672.9076837967. The cubic root of 312331666 is about 678.4825345903.

Adding to 312331666 its reverse (666133213), we get a palindrome (978464879).

The spelling of 312331666 in words is "three hundred twelve million, three hundred thirty-one thousand, six hundred sixty-six".