3925781643 has 16 divisors (see below), whose sum is σ = 6109424640. Its totient is φ = 2195573376.

The previous prime is 3925781641. The next prime is 3925781647. The reversal of 3925781643 is 3461875293.

It is not a de Polignac number, because 3925781643 - 2¹ = 3925781641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 3925781592 and 3925781601.

It is not an unprimeable number, because it can be changed into a prime (3925781641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1987758 + ... + 1989731.

It is an arithmetic number, because the mean of its divisors is an integer number (381839040).

Almost surely, 2^3925781643 is an apocalyptic number.

3925781643 is a deficient number, since it is larger than the sum of its proper divisors (2183642997).

3925781643 is a wasteful number, since it uses less digits than its factorization.

3925781643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3977546.

The product of its digits is 1088640, while the sum is 48.

The square root of 3925781643 is about 62656.0583104300. The cubic root of 3925781643 is about 1577.5218379156.

The spelling of 3925781643 in words is "three billion, nine hundred twenty-five million, seven hundred eighty-one thousand, six hundred forty-three".