3971516643 has 16 divisors (see below), whose sum is σ = 5887564800. Its totient is φ = 2645951400.

The previous prime is 3971516641. The next prime is 3971516657. The reversal of 3971516643 is 3466151793.

It is a happy number.

3971516643 is a `hidden beast` number, since 3 + 9 + 71 + 516 + 64 + 3 = 666.

3971516643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 3971516643 - 2¹ = 3971516641 is a prime.

It is a hoax number, since the sum of its digits (45) 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 (3971516641) 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, 5083 + ... + 89268.

It is an arithmetic number, because the mean of its divisors is an integer number (367972800).

Almost surely, 2^3971516643 is an apocalyptic number.

3971516643 is a deficient number, since it is larger than the sum of its proper divisors (1916048157).

3971516643 is a wasteful number, since it uses less digits than its factorization.

3971516643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95919 (or 95913 counting only the distinct ones).

The product of its digits is 408240, while the sum is 45.

The square root of 3971516643 is about 63019.9701919955. The cubic root of 3971516643 is about 1583.6241970338.

The spelling of 3971516643 in words is "three billion, nine hundred seventy-one million, five hundred sixteen thousand, six hundred forty-three".