728857321537 has 2 divisors, whose sum is σ = 728857321538. Its totient is φ = 728857321536.

The previous prime is 728857321519. The next prime is 728857321561. The reversal of 728857321537 is 735123758827.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 461365619121 + 267491702416 = 679239^2 + 517196^2 .

It is a cyclic number.

It is not a de Polignac number, because 728857321537 - 2¹⁵ = 728857288769 is a prime.

It is not a weakly prime, because it can be changed into another prime (728857322537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 364428660768 + 364428660769.

It is an arithmetic number, because the mean of its divisors is an integer number (364428660769).

Almost surely, 2^728857321537 is an apocalyptic number.

It is an amenable number.

728857321537 is a deficient number, since it is larger than the sum of its proper divisors (1).

728857321537 is an equidigital number, since it uses as much as digits as its factorization.

728857321537 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19756800, while the sum is 58.

The spelling of 728857321537 in words is "seven hundred twenty-eight billion, eight hundred fifty-seven million, three hundred twenty-one thousand, five hundred thirty-seven".