1091021819280 has 80 divisors (see below), whose sum is σ = 3382983951360. Its totient is φ = 290868931584.

The previous prime is 1091021819273. The next prime is 1091021819311. The reversal of 1091021819280 is 829181201901.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×1091021819280² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 451644 + ... + 1544676.

It is an arithmetic number, because the mean of its divisors is an integer number (42287299392).

Almost surely, 2^{1091021819280} is an apocalyptic number.

1091021819280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1091021819280 is an abundant number, since it is smaller than the sum of its proper divisors (2291962132080).

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

1091021819280 is a wasteful number, since it uses less digits than its factorization.

1091021819280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1097208 (or 1097202 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 42.

The spelling of 1091021819280 in words is "one trillion, ninety-one billion, twenty-one million, eight hundred nineteen thousand, two hundred eighty".