1091190921 has 8 divisors (see below), whose sum is σ = 1464686400. Its totient is φ = 722578032.

The previous prime is 1091190907. The next prime is 1091190923. The reversal of 1091190921 is 1290911901.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1091190921 - 2⁶ = 1091190857 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1091190923) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1220125 + ... + 1221018.

It is an arithmetic number, because the mean of its divisors is an integer number (183085800).

Almost surely, 2^1091190921 is an apocalyptic number.

It is an amenable number.

1091190921 is a deficient number, since it is larger than the sum of its proper divisors (373495479).

1091190921 is a wasteful number, since it uses less digits than its factorization.

1091190921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2441295.

The product of its (nonzero) digits is 1458, while the sum is 33.

The square root of 1091190921 is about 33033.1790931481. The cubic root of 1091190921 is about 1029.5171397451.

The spelling of 1091190921 in words is "one billion, ninety-one million, one hundred ninety thousand, nine hundred twenty-one".