728925391 has 4 divisors (see below), whose sum is σ = 729111312. Its totient is φ = 728739472.

The previous prime is 728925389. The next prime is 728925403. The reversal of 728925391 is 193529827.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 193529827 = 109 ⋅1775503.

It is a cyclic number.

It is not a de Polignac number, because 728925391 - 2¹ = 728925389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728925311) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86950 + ... + 94963.

It is an arithmetic number, because the mean of its divisors is an integer number (182277828).

Almost surely, 2^728925391 is an apocalyptic number.

728925391 is a deficient number, since it is larger than the sum of its proper divisors (185921).

728925391 is a wasteful number, since it uses less digits than its factorization.

728925391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185920.

The product of its digits is 272160, while the sum is 46.

The square root of 728925391 is about 26998.6183164991. The cubic root of 728925391 is about 899.9692956603.

It can be divided in two parts, 728925 and 391, that added together give a square (729316 = 854²).

The spelling of 728925391 in words is "seven hundred twenty-eight million, nine hundred twenty-five thousand, three hundred ninety-one".