3861861686244 has 81 divisors (see below), whose sum is σ = 9857234034921. Its totient is φ = 1274839892640.

The previous prime is 3861861686213. The next prime is 3861861686257. The reversal of 3861861686244 is 4426861681683.

It is a happy number.

The square root of 3861861686244 is 1965162.

It is a perfect power (a square), and thus also a powerful number.

3861861686244 is a `hidden beast` number, since 3 + 8 + 6 + 1 + 8 + 616 + 8 + 6 + 2 + 4 + 4 = 666.

3861861686244 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 3682323047844 + 179538638400 = 1918938^2 + 423720^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1261632474 + ... + 1261635534.

Almost surely, 2^{3861861686244} is an apocalyptic number.

3861861686244 is the 1965162-nd square number.

It is an amenable number.

3861861686244 is an abundant number, since it is smaller than the sum of its proper divisors (5995372348677).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3861861686244 is an equidigital number, since it uses as much as digits as its factorization.

3861861686244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6346 (or 3173 counting only the distinct ones).

The product of its digits is 63700992, while the sum is 63.

The spelling of 3861861686244 in words is "three trillion, eight hundred sixty-one billion, eight hundred sixty-one million, six hundred eighty-six thousand, two hundred forty-four".