728916191 has 4 divisors (see below), whose sum is σ = 771793632. Its totient is φ = 686038752.

The previous prime is 728916137. The next prime is 728916203. The reversal of 728916191 is 191619827.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 191619827 = 7 ⋅27374261.

It is a cyclic number.

It is not a de Polignac number, because 728916191 - 2⁶ = 728916127 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 (728916101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21438695 + ... + 21438728.

It is an arithmetic number, because the mean of its divisors is an integer number (192948408).

Almost surely, 2^728916191 is an apocalyptic number.

728916191 is a deficient number, since it is larger than the sum of its proper divisors (42877441).

728916191 is a wasteful number, since it uses less digits than its factorization.

728916191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42877440.

The product of its digits is 54432, while the sum is 44.

The square root of 728916191 is about 26998.4479368722. The cubic root of 728916191 is about 899.9655093778.

The spelling of 728916191 in words is "seven hundred twenty-eight million, nine hundred sixteen thousand, one hundred ninety-one".