3121999966 has 16 divisors (see below), whose sum is σ = 4716750384. Its totient is φ = 1549790784.

The previous prime is 3121999961. The next prime is 3122000009. The reversal of 3121999966 is 6699991213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3121999961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 146826 + ... + 166738.

It is an arithmetic number, because the mean of its divisors is an integer number (294796899).

Almost surely, 2^3121999966 is an apocalyptic number.

3121999966 is a deficient number, since it is larger than the sum of its proper divisors (1594750418).

3121999966 is a wasteful number, since it uses less digits than its factorization.

3121999966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20475.

The product of its digits is 1417176, while the sum is 55.

The square root of 3121999966 is about 55874.8598745447. The cubic root of 3121999966 is about 1461.5408711731.

The spelling of 3121999966 in words is "three billion, one hundred twenty-one million, nine hundred ninety-nine thousand, nine hundred sixty-six".