1985963986 has 8 divisors (see below), whose sum is σ = 3051603324. Its totient is φ = 968762880.

The previous prime is 1985963981. The next prime is 1985964023. The reversal of 1985963986 is 6893695891.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1973580625 + 12383361 = 44425^2 + 3519^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (1985963981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12109455 + ... + 12109618.

Almost surely, 2^1985963986 is an apocalyptic number.

1985963986 is a deficient number, since it is larger than the sum of its proper divisors (1065639338).

1985963986 is a wasteful number, since it uses less digits than its factorization.

1985963986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24219116.

The product of its digits is 25194240, while the sum is 64.

The square root of 1985963986 is about 44564.1558430091. The cubic root of 1985963986 is about 1256.9667497297.

It can be divided in two parts, 19859 and 63986, that added together give a triangular number (83845 = T₄₀₉).

The spelling of 1985963986 in words is "one billion, nine hundred eighty-five million, nine hundred sixty-three thousand, nine hundred eighty-six".