728791663 has 8 divisors (see below), whose sum is σ = 755211600. Its totient is φ = 702457728.

The previous prime is 728791643. The next prime is 728791667. The reversal of 728791663 is 366197827.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-728791663 is a prime.

It is a super-2 number, since 2×728791663² = 1062274576116611138, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728791667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3993 + ... + 38386.

It is an arithmetic number, because the mean of its divisors is an integer number (94401450).

Almost surely, 2^728791663 is an apocalyptic number.

728791663 is a deficient number, since it is larger than the sum of its proper divisors (26419937).

728791663 is a wasteful number, since it uses less digits than its factorization.

728791663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43001.

The product of its digits is 762048, while the sum is 49.

The square root of 728791663 is about 26996.1416317221. The cubic root of 728791663 is about 899.9142564405.

The spelling of 728791663 in words is "seven hundred twenty-eight million, seven hundred ninety-one thousand, six hundred sixty-three".