3181336661 has 4 divisors (see below), whose sum is σ = 3181531500. Its totient is φ = 3181141824.

The previous prime is 3181336637. The next prime is 3181336663. The reversal of 3181336661 is 1666331813.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1666331813 = 5113 ⋅325901.

It can be written as a sum of positive squares in 2 ways, for example, as 2673510436 + 507826225 = 51706^2 + 22535^2 .

It is a cyclic number.

It is not a de Polignac number, because 3181336661 - 2¹⁴ = 3181320277 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3181336663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70436 + ... + 106413.

It is an arithmetic number, because the mean of its divisors is an integer number (795382875).

Almost surely, 2^3181336661 is an apocalyptic number.

It is an amenable number.

3181336661 is a deficient number, since it is larger than the sum of its proper divisors (194839).

3181336661 is a wasteful number, since it uses less digits than its factorization.

3181336661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194838.

The product of its digits is 46656, while the sum is 38.

The square root of 3181336661 is about 56403.3390944189. The cubic root of 3181336661 is about 1470.7421647655.

The spelling of 3181336661 in words is "three billion, one hundred eighty-one million, three hundred thirty-six thousand, six hundred sixty-one".