3891881984 has 48 divisors (see below), whose sum is σ = 7909689060. Its totient is φ = 1913978880.

The previous prime is 3891881971. The next prime is 3891882017. The reversal of 3891881984 is 4891881983.

It can be written as a sum of positive squares in 2 ways, for example, as 3211715584 + 680166400 = 56672^2 + 26080^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 109352 + ... + 140504.

Almost surely, 2^3891881984 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3891881984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3954844530).

3891881984 is an abundant number, since it is smaller than the sum of its proper divisors (4017807076).

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

3891881984 is an equidigital number, since it uses as much as digits as its factorization.

3891881984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31236 (or 31216 counting only the distinct ones).

The product of its digits is 3981312, while the sum is 59.

The square root of 3891881984 is about 62384.9499799431. The cubic root of 3891881984 is about 1572.9679996971.

Subtracting 3891881984 from its reverse (4891881983), we obtain a palindrome (999999999).

The spelling of 3891881984 in words is "three billion, eight hundred ninety-one million, eight hundred eighty-one thousand, nine hundred eighty-four".