1028543561 has 4 divisors (see below), whose sum is σ = 1028610324. Its totient is φ = 1028476800.

The previous prime is 1028543543. The next prime is 1028543563. The reversal of 1028543561 is 1653458201.

1028543561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1653458201 = 23 ⋅71889487.

It can be written as a sum of positive squares in 2 ways, for example, as 474411961 + 554131600 = 21781^2 + 23540^2 .

It is a cyclic number.

It is not a de Polignac number, because 1028543561 - 2⁶ = 1028543497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1028543563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2801 + ... + 45441.

It is an arithmetic number, because the mean of its divisors is an integer number (257152581).

Almost surely, 2^1028543561 is an apocalyptic number.

It is an amenable number.

1028543561 is a deficient number, since it is larger than the sum of its proper divisors (66763).

1028543561 is an equidigital number, since it uses as much as digits as its factorization.

1028543561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66762.

The product of its (nonzero) digits is 28800, while the sum is 35.

The square root of 1028543561 is about 32070.9145644461. The cubic root of 1028543561 is about 1009.4254029996.

The spelling of 1028543561 in words is "one billion, twenty-eight million, five hundred forty-three thousand, five hundred sixty-one".