728122091989 has 16 divisors (see below), whose sum is σ = 762741480960. Its totient is φ = 694254401280.

The previous prime is 728122091971. The next prime is 728122092023. The reversal of 728122091989 is 989190221827.

It is a cyclic number.

It is not a de Polignac number, because 728122091989 - 2¹³ = 728122083797 is a prime.

It is a super-2 number, since 2×728122091989² (a number of 25 digits) 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 (728122091089) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 314529 + ... + 1247065.

It is an arithmetic number, because the mean of its divisors is an integer number (47671342560).

Almost surely, 2^728122091989 is an apocalyptic number.

It is an amenable number.

728122091989 is a deficient number, since it is larger than the sum of its proper divisors (34619388971).

728122091989 is a wasteful number, since it uses less digits than its factorization.

728122091989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 932940.

The product of its (nonzero) digits is 2612736, while the sum is 58.

The spelling of 728122091989 in words is "seven hundred twenty-eight billion, one hundred twenty-two million, ninety-one thousand, nine hundred eighty-nine".