728221751 has 2 divisors, whose sum is σ = 728221752. Its totient is φ = 728221750.

The previous prime is 728221723. The next prime is 728221783. The reversal of 728221751 is 157122827.

It is a weak prime.

It is an emirp because it is prime and its reverse (157122827) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 728221751 - 2¹⁴ = 728205367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (728220751) 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 as a sum of consecutive naturals, namely, 364110875 + 364110876.

It is an arithmetic number, because the mean of its divisors is an integer number (364110876).

Almost surely, 2^728221751 is an apocalyptic number.

728221751 is a deficient number, since it is larger than the sum of its proper divisors (1).

728221751 is an equidigital number, since it uses as much as digits as its factorization.

728221751 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15680, while the sum is 35.

The square root of 728221751 is about 26985.5841330144. The cubic root of 728221751 is about 899.6796188864.

The spelling of 728221751 in words is "seven hundred twenty-eight million, two hundred twenty-one thousand, seven hundred fifty-one".