728216428 has 6 divisors (see below), whose sum is σ = 1274378756. Its totient is φ = 364108212.

The previous prime is 728216407. The next prime is 728216431. The reversal of 728216428 is 824612827.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 91027050 + ... + 91027057.

Almost surely, 2^728216428 is an apocalyptic number.

It is an amenable number.

728216428 is a deficient number, since it is larger than the sum of its proper divisors (546162328).

728216428 is a wasteful number, since it uses less digits than its factorization.

728216428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182054111 (or 182054109 counting only the distinct ones).

The product of its digits is 86016, while the sum is 40.

The square root of 728216428 is about 26985.4855061012. The cubic root of 728216428 is about 899.6774267857.

It can be divided in two parts, 728 and 216428, that added together give a square (217156 = 466²).

The spelling of 728216428 in words is "seven hundred twenty-eight million, two hundred sixteen thousand, four hundred twenty-eight".