1028980991 has 4 divisors (see below), whose sum is σ = 1034929032. Its totient is φ = 1023032952.

The previous prime is 1028980951. The next prime is 1028981017. The reversal of 1028980991 is 1990898201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1990898201 = 53 ⋅37564117.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1028980991 is a prime.

It is a Duffinian number.

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1028980921) 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 in 3 ways as a sum of consecutive naturals, for example, 2973761 + ... + 2974106.

It is an arithmetic number, because the mean of its divisors is an integer number (258732258).

Almost surely, 2^1028980991 is an apocalyptic number.

1028980991 is a deficient number, since it is larger than the sum of its proper divisors (5948041).

1028980991 is an equidigital number, since it uses as much as digits as its factorization.

1028980991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5948040.

The product of its (nonzero) digits is 93312, while the sum is 47.

The square root of 1028980991 is about 32077.7335701885. The cubic root of 1028980991 is about 1009.5684824599.

The spelling of 1028980991 in words is "one billion, twenty-eight million, nine hundred eighty thousand, nine hundred ninety-one".