1091020128 has 96 divisors (see below), whose sum is σ = 3288781440. Its totient is φ = 313205760.

The previous prime is 1091020121. The next prime is 1091020171. The reversal of 1091020128 is 8210201901.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×1091020128² = 2380649839402272768, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a junction number, because it is equal to n+sod(n) for n = 1091020098 and 1091020107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091020121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7125 + ... + 47252.

It is an arithmetic number, because the mean of its divisors is an integer number (34258140).

Almost surely, 2^1091020128 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1091020128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1644390720).

1091020128 is an abundant number, since it is smaller than the sum of its proper divisors (2197761312).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1091020128 is a wasteful number, since it uses less digits than its factorization.

1091020128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54420 (or 54412 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 24.

The square root of 1091020128 is about 33030.5938184587. The cubic root of 1091020128 is about 1029.4634236654.

The spelling of 1091020128 in words is "one billion, ninety-one million, twenty thousand, one hundred twenty-eight".