3915721872 has 80 divisors (see below), whose sum is σ = 11247544000. Its totient is φ = 1304315136.

The previous prime is 3915721861. The next prime is 3915721889. The reversal of 3915721872 is 2781275193.

3915721872 is a `hidden beast` number, since 3 + 9 + 1 + 572 + 1 + 8 + 72 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 900279 + ... + 904617.

It is an arithmetic number, because the mean of its divisors is an integer number (140594300).

Almost surely, 2^3915721872 is an apocalyptic number.

It is an amenable number.

3915721872 is an abundant number, since it is smaller than the sum of its proper divisors (7331822128).

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

3915721872 is a wasteful number, since it uses less digits than its factorization.

3915721872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6445 (or 6433 counting only the distinct ones).

The product of its digits is 211680, while the sum is 45.

The square root of 3915721872 is about 62575.7290968311. The cubic root of 3915721872 is about 1576.1732247088.

The spelling of 3915721872 in words is "three billion, nine hundred fifteen million, seven hundred twenty-one thousand, eight hundred seventy-two".