1191023 has 4 divisors (see below), whose sum is σ = 1193640. Its totient is φ = 1188408.

The previous prime is 1191019. The next prime is 1191031. The reversal of 1191023 is 3201911.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1191023 - 2² = 1191019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1190992 and 1191010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1191013) 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 3 ways as a sum of consecutive naturals, for example, 428 + ... + 1601.

It is an arithmetic number, because the mean of its divisors is an integer number (298410).

2^1191023 is an apocalyptic number.

1191023 is a deficient number, since it is larger than the sum of its proper divisors (2617).

1191023 is an equidigital number, since it uses as much as digits as its factorization.

1191023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2616.

The product of its (nonzero) digits is 54, while the sum is 17.

The square root of 1191023 is about 1091.3400020159. The cubic root of 1191023 is about 106.0002076654. Note that the first 3 decimals are identical.

Adding to 1191023 its reverse (3201911), we get a palindrome (4392934).

The spelling of 1191023 in words is "one million, one hundred ninety-one thousand, twenty-three".