3971638860 has 96 divisors (see below), whose sum is σ = 12737088000. Its totient is φ = 905814528.

The previous prime is 3971638823. The next prime is 3971638861. The reversal of 3971638860 is 688361793.

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (3971638861) 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 31 ways as a sum of consecutive naturals, for example, 186016 + ... + 206264.

It is an arithmetic number, because the mean of its divisors is an integer number (132678000).

Almost surely, 2^3971638860 is an apocalyptic number.

3971638860 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3971638860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6368544000).

3971638860 is an abundant number, since it is smaller than the sum of its proper divisors (8765449140).

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

3971638860 is a wasteful number, since it uses less digits than its factorization.

3971638860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20735 (or 20733 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 51.

The square root of 3971638860 is about 63020.9398533535. The cubic root of 3971638860 is about 1583.6404413581.

The spelling of 3971638860 in words is "three billion, nine hundred seventy-one million, six hundred thirty-eight thousand, eight hundred sixty".