3947690728 has 32 divisors (see below), whose sum is σ = 7610587560. Its totient is φ = 1918321920.

The previous prime is 3947690713. The next prime is 3947690731. The reversal of 3947690728 is 8270967493.

It can be written as a sum of positive squares in 4 ways, for example, as 3906500004 + 41190724 = 62502^2 + 6418^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 271450 + ... + 285622.

Almost surely, 2^3947690728 is an apocalyptic number.

It is an amenable number.

3947690728 is a deficient number, since it is larger than the sum of its proper divisors (3662896832).

3947690728 is a wasteful number, since it uses less digits than its factorization.

3947690728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15157 (or 15153 counting only the distinct ones).

The product of its (nonzero) digits is 4572288, while the sum is 55.

The square root of 3947690728 is about 62830.6511823648. The cubic root of 3947690728 is about 1580.4510179606.

The spelling of 3947690728 in words is "three billion, nine hundred forty-seven million, six hundred ninety thousand, seven hundred twenty-eight".