3928782321 has 12 divisors (see below), whose sum is σ = 5678982400. Its totient is φ = 2617307640.

The previous prime is 3928782313. The next prime is 3928782349. The reversal of 3928782321 is 1232878293.

It is not a de Polignac number, because 3928782321 - 2³ = 3928782313 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (3928782301) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 143425 + ... + 168606.

Almost surely, 2^3928782321 is an apocalyptic number.

It is an amenable number.

3928782321 is a deficient number, since it is larger than the sum of its proper divisors (1750200079).

3928782321 is a wasteful number, since it uses less digits than its factorization.

3928782321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313436 (or 313433 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 3928782321 is about 62679.9993698149. Note that the first 3 decimals coincide. The cubic root of 3928782321 is about 1577.9236627377.

The spelling of 3928782321 in words is "three billion, nine hundred twenty-eight million, seven hundred eighty-two thousand, three hundred twenty-one".