1091199121 has 4 divisors (see below), whose sum is σ = 1091718144. Its totient is φ = 1090680100.

The previous prime is 1091199107. The next prime is 1091199167. The reversal of 1091199121 is 1219911901.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1091199121 - 2²⁹ = 554328209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1091199521) 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, 256345 + ... + 260566.

It is an arithmetic number, because the mean of its divisors is an integer number (272929536).

Almost surely, 2^1091199121 is an apocalyptic number.

It is an amenable number.

1091199121 is a deficient number, since it is larger than the sum of its proper divisors (519023).

1091199121 is an equidigital number, since it uses as much as digits as its factorization.

1091199121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 519022.

The product of its (nonzero) digits is 1458, while the sum is 34.

The square root of 1091199121 is about 33033.3032105480. The cubic root of 1091199121 is about 1029.5197185848.

The spelling of 1091199121 in words is "one billion, ninety-one million, one hundred ninety-nine thousand, one hundred twenty-one".