331666018 has 4 divisors (see below), whose sum is σ = 497499030. Its totient is φ = 165833008.

The previous prime is 331665979. The next prime is 331666031. The reversal of 331666018 is 810666133.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 810666133 = 107 ⋅7576319.

It can be written as a sum of positive squares in only one way, i.e., 247338529 + 84327489 = 15727^2 + 9183^2 .

It is a super-2 number, since 2×331666018² = 220004694991952648, which contains 22 as substring.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 82916503 + ... + 82916506.

Almost surely, 2^331666018 is an apocalyptic number.

331666018 is a deficient number, since it is larger than the sum of its proper divisors (165833012).

331666018 is a wasteful number, since it uses less digits than its factorization.

331666018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165833011.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 331666018 is about 18211.7000304749. The cubic root of 331666018 is about 692.2032895892.

The spelling of 331666018 in words is "three hundred thirty-one million, six hundred sixty-six thousand, eighteen".