3945728 has 18 divisors (see below), whose sum is σ = 7876554. Its totient is φ = 1972736.

The previous prime is 3945727. The next prime is 3945731. The reversal of 3945728 is 8275493.

It can be written as a sum of positive squares in only one way, i.e., 3810304 + 135424 = 1952^2 + 368^2 .

It is a junction number, because it is equal to n+sod(n) for n = 3945691 and 3945700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3945727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7451 + ... + 7962.

Almost surely, 2^3945728 is an apocalyptic number.

It is an amenable number.

3945728 is a deficient number, since it is larger than the sum of its proper divisors (3930826).

3945728 is an equidigital number, since it uses as much as digits as its factorization.

3945728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15429 (or 15415 counting only the distinct ones).

The product of its digits is 60480, while the sum is 38.

The square root of 3945728 is about 1986.3856624533. The cubic root of 3945728 is about 158.0189049643.

The spelling of 3945728 in words is "three million, nine hundred forty-five thousand, seven hundred twenty-eight".