1011728657 has 4 divisors (see below), whose sum is σ = 1011937716. Its totient is φ = 1011519600.

The previous prime is 1011728621. The next prime is 1011728687. The reversal of 1011728657 is 7568271101.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 916938961 + 94789696 = 30281^2 + 9736^2 .

It is a cyclic number.

It is not a de Polignac number, because 1011728657 - 2²⁰ = 1010680081 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1011728657.

It is not an unprimeable number, because it can be changed into a prime (1011728687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97094 + ... + 107007.

It is an arithmetic number, because the mean of its divisors is an integer number (252984429).

Almost surely, 2^1011728657 is an apocalyptic number.

It is an amenable number.

1011728657 is a deficient number, since it is larger than the sum of its proper divisors (209059).

1011728657 is an equidigital number, since it uses as much as digits as its factorization.

1011728657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209058.

The product of its (nonzero) digits is 23520, while the sum is 38.

The square root of 1011728657 is about 31807.6823581977. The cubic root of 1011728657 is about 1003.8943665550.

Adding to 1011728657 its reverse (7568271101), we get a palindrome (8579999758).

The spelling of 1011728657 in words is "one billion, eleven million, seven hundred twenty-eight thousand, six hundred fifty-seven".